UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 8-K

CURRENT REPORT
Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) ~~July~~December 1112, 2005

GMAC Commercial Mortgage Securities, Inc.
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction
of incorporation)

333-123974-01
(Commission
File Number)

23-2811925
(IRS Employer
Identification No.)

200 Witmer Road, Horsham, Pennsylvania
(Address of principal executive offices)

19044
(Zip Code)

Registrant's telephone number, including area code 215-328-3164

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

[ ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

[ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Section 8 - Other Events

Item 8.01. Other Events.

This current report on Form 8-K relates to the monthly distribution reported to the holders of GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates, ~~series~~Series 2005-C1, which was made on ~~July~~December 1112, 2005.

Section 9 - Financial Statements and Exhibits

Item 9.01 Financial Statements and Exhibits.

(Exhibit No. Description) 99.1 Monthly distribution report pursuant to section 4.02 of the Pooling and Servicing Agreement for the distribution on ~~July~~December 1112, 2005.

(Exhibit No. Description)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

LASALLE BANK NATIONAL ASSOCIATION, IN ITS CAPACITY AS TRUSTEE UNDER THE POOLING AND SERVICING AGREEMENT ON BEHALF OF GMAC COMMERCIAL MORTGAGE SECURITIES, INC., REGISTRANT

By: /s/ Russell Goldenberg Russell Goldenberg Group Senior Vice President Date: ~~July~~December 1415, 2005

GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Reporting Package Table of Contents Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Administrator:Ann Kelly 312.904.1487ann.kelly@abnamro.com Analyst:Clifford Song 714.259.6244 Clifford.Song@abnamro.com Statement Date: 135 S. LaSalle Street, Suite 1625Chicago, IL 60603USA Statements to CertificateholdersCash Reconciliation SummaryBond Interest ReconciliationShortfall Summary Report Rating Information Asset-Backed Facts ~ 15 Month Loan Status SummaryAsset-Backed Facts ~ 15 Month Loan Payoff/Loss Summary Mortgage Loan CharacteristicsDelinquent Loan DetailHistorical Collateral Prepayment Page 2-6Page 7-9Page 10Page 11 Page 12-13 Page 14-16Page 17-19 Page 20-22Page 23 Page 24 Loan Level Detail Specially Serviced (Part I) - Loan DetailSpecially Serviced (Part II) - Servicer CommentsHistorical REO Report Modified Loan DetailRealized Loss DetailAppraisal Reduction Detail Page 25-28 Page 29Page 30Page 31 Page 32Page 33Page 34 Page(s) Information is available for this issue from the following sources Issue Id: Monthly Data FileName: GMAC05C1 GMAC05C1_200507_3.ZIP Closing Date: First Payment Date: Rated Final Payment: Date: 6-Jun-0511-Jul-05 11-May-43 Parties to The Transaction Issuer: GMAC Commercial Mortgage Securities, Inc. Depositor: GMAC Commercial Mortgage Securities, Inc. Underwriter: Deutsche Bank Securities Inc./GMAC Commercial Holding Capital Markets Corp./Morgan Stanley & Co. Incorporated Master Servicer: GMAC Commercial Mortgage Corporation Special Servicer: GMAC Commercial Mortgage Corporation Rating Agency: Fitch Ratings/Standard & Poor's Ratings Services 800.246.5761 LaSalle Factor Line LaSalle Web Site Servicer Web Site www.gmaccm.com www.etrustee.net Page 1 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 5.503992% 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates Series 2005-C1 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate 94 REMIC III Statement Date: ABN AMRO Acct: 722718.1 1000.000000000 9.740461275 0.000000000 990.259538725 3.506666667 Fixed 0.00 0.00 0.000000000 4.2080000000% 0.000000000 361849M41 A-1 61,200,000.00 596,116.23 0.00 60,603,883.77 214,608.00 61,200,000.00 1000.000000000 0.175619654 0.000000000 999.824380346 3.845833321 Fixed 0.00 0.00 0.000000000 4.6150000000% 0.000000000 361849M58 A-1A 344,507,000.00 60,502.20 0.00 344,446,497.80 1,324,916.50 344,507,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.725833333 Fixed 0.00 0.00 0.000000000 4.4710000000% 0.000000000 361849M66 A-2 300,000,000.00 0.00 0.00 300,000,000.00 1,117,750.00 300,000,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.781666684 Fixed 0.00 0.00 0.000000000 4.5380000000% 0.000000000 361849M74 A-3 187,300,000.00 0.00 0.00 187,300,000.00 708,306.17 187,300,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.849166667 Fixed 0.00 0.00 0.000000000 4.6190000000% 0.000000000 361849M82 A-4 68,100,000.00 0.00 0.00 68,100,000.00 262,128.25 68,100,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.914166640 Fixed 0.00 0.00 0.000000000 4.6970000000% 0.000000000 361849Q21 A-5 157,393,000.00 0.00 0.00 157,393,000.00 616,062.43 157,393,000.00 1000.000000000 0.000000000 0.000000000 999.589063167 0.079820612 0.00 0.00 0.000000000 0.0957847339% 0.000000000 N 361849N65 X-1 1,597,857,327.00 0.00 0.00 1,597,200,708.57 127,541.95 1,597,857,327.00 1000.000000000 0.000000000 0.000000000 1000.000000000 0.648352960 0.00 0.00 0.000000000 0.7780235519% 0.000000000 N 361849M90 X-2 1,490,771,000.00 0.00 0.00 1,490,771,000.00 966,545.79 1,490,771,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.961666677 Fixed 0.00 0.00 0.000000000 4.7540000000% 0.000000000 361849Q39 A-M 159,785,000.00 0.00 0.00 159,785,000.00 633,014.91 159,785,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.004999961 Fixed 0.00 0.00 0.000000000 4.8060000000% 0.000000000 361849N24 A-J 127,829,000.00 0.00 0.00 127,829,000.00 511,955.14 127,829,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.113333333 Fixed 0.00 0.00 0.000000000 4.9360000000% 0.000000000 361849N32 B 33,954,000.00 0.00 0.00 33,954,000.00 139,664.12 33,954,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.156666389 4.9880000000% 0.00 0.00 0.000000000 4.9880000000% 0.000000000 361849N40 C 11,984,000.00 0.00 0.00 11,984,000.00 49,813.49 11,984,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.214166806 5.0570000000% 0.00 0.00 0.000000000 5.0570000000% 0.000000000 361849N57 D 23,968,000.00 0.00 0.00 23,968,000.00 101,005.15 23,968,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.295833281 5.1550000000% 0.00 0.00 0.000000000 5.1550000000% 0.000000000 361849N73 E 15,979,000.00 0.00 0.00 15,979,000.00 68,643.12 15,979,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.033333333 4.8400000000% 0.00 0.00 0.000000000 4.8400000000% 0.000000000 361849N81 F 15,978,000.00 0.00 0.00 15,978,000.00 64,444.60 15,978,000.00 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 2 of 34 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 5.503992% 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates Series 2005-C1 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate 94 REMIC III Statement Date: ABN AMRO Acct: 722718.1 1000.000000000 0.000000000 0.000000000 1000.000000000 4.097499844 4.9170000000% 0.00 0.00 0.000000000 4.9170000000% 0.000000000 361849N99 G 15,979,000.00 0.00 0.00 15,979,000.00 65,473.95 15,979,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 4.390000000 5.2680000000% 0.00 0.00 0.000000000 5.2680000000% 0.000000000 361849P22 H 19,973,000.00 0.00 0.00 19,973,000.00 87,681.47 19,973,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729167223 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P30 J 5,992,000.00 0.00 0.00 5,992,000.00 22,345.17 5,992,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729167223 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P48 K 5,992,000.00 0.00 0.00 5,992,000.00 22,345.17 5,992,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729166354 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P55 L 7,989,000.00 0.00 0.00 7,989,000.00 29,792.31 7,989,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729166458 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P63 M 3,995,000.00 0.00 0.00 3,995,000.00 14,898.02 3,995,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729166458 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P71 N 3,995,000.00 0.00 0.00 3,995,000.00 14,898.02 3,995,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729166249 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P89 O 3,994,000.00 0.00 0.00 3,994,000.00 14,894.29 3,994,000.00 1000.000000000 0.000000000 0.000000000 1000.000000000 3.729166654 4.4750000000% 0.00 0.00 0.000000000 4.4750000000% 0.000000000 361849P97 P 21,971,327.00 0.00 0.00 21,971,327.00 81,934.74 21,971,327.00 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 111322640 R-III 0.00 0.00 0.00 0.00 0.00 0.00 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 111322624 R-I 0.00 0.00 0.00 0.00 0.00 0.00 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 111322632 R-II 0.00 0.00 0.00 0.00 0.00 0.00 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 3 of 34 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 5.503992% 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates Series 2005-C1 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate 94 REMIC III Statement Date: ABN AMRO Acct: 722718.1 Total P&I Payment 0.00 0.00 1,597,857,327.00 1,597,857,327.00 7,917,281.19 Total 1,597,200,708.57 656,618.43 0.00 7,260,662.76 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 4 of 34 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 5.503992% 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates Series 2005-C1 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate 94 Grantor Trust Q Statement Date: ABN AMRO Acct: 722718.1 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 111322608 Q 0.00 0.00 0.00 0.00 0.00 0.00 Total P&I Payment 0.00 0.00 0.00 0.00 0.00 Total 0.00 0.00 0.00 0.00 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 5 of 34 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class Class CUSIP Original Opening Principal Principal Negative Closing Interest Interest Pass-Through Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Per $ 1000 Next Rate(3) WAC:WAMM: Payment Date:Prior Payment:Next Payment:Record Date: 5.503992% 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 GMAC Commercial Mortgage Securities, Inc. Mortgage Pass-Through Certificates Series 2005-C1 Face Value (1) Balance Payment Adj. or Loss Amortization Balance Payment (2) Adjustment Rate 94 Grantor Trust W Statement Date: ABN AMRO Acct: 722718.1 0.000000000 0.000000000 0.000000000 0.000000000 0.000000000 0.00 0.00 0.000000000 N/A 0.000000000 111322616 W 0.00 0.00 0.00 0.00 0.00 0.00 Total P&I Payment 0.00 0.00 0.00 0.00 0.00 Total 0.00 0.00 0.00 0.00 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 6 of 34 Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Statement Date: Cash Reconciliation Summary Current Scheduled Interest Interest Summary Less Deferred Interest Plus Gross Advance Interest Less PPIS Reducing Scheduled Int 7,328,828.42 0.000.00 Less ASER Interest Adv Reduction 0.00 Less Other Adjustment 0.00 Total 7,328,828.42 Unscheduled Interest:Prepayment Penalties 0.00 Yield Maintenance Penalties 0.00 Other Interest Proceeds 0.00 Total 0.00 Less Fees & Expenses Paid By/To Servicer Less Fee Paid To Servicer Less Fee Strips Paid by Servicer Special Servicing Fees Interest Due Serv on Advances Recoup of Prior Advances Misc. Fees & Expenses Total Unscheduled Fees & ExpensesTotal Interest Due Trust Less Fees & Expenses Paid By/To TrustTrustee FeeFee StripsMisc. FeesInterest Reserve Withholding Plus Interest Reserve DepositTotal Total Interest Due Certs Principal Summary Scheduled Principal:Current Scheduled PrincipalAdvanced Scheduled PrincipalScheduled PrincipalUnscheduled Principal:CurtailmentsPrepayments in FullLiquidation ProceedsRepurchase ProceedsOther Principal ProceedsTotal Unscheduled Principal Remittance Principal Remittance P&I Due Trust Remittance P&I Due Certs Pool Balance Summary Beginning PoolScheduled PrincipalUnscheduled PrincipalDeferred InterestLiquidationsRepurchases Ending Pool Balance Count Principal Interest Prior OutstandingPlus Current PeriodLess Recovered Ending Outstanding Servicing Fee Summary Current Servicing FeesPlus Fees Advanced for PPISLess Reduction for PPISPlus Delinquent Servicing Fees Total Servicing Fees PPIS Summary Gross PPISReduced by PPIEReduced by Shortfalls in FeesReduced by Other Amounts PPIS Reducing ScheduledInterest PPIS Reducing Servicing FeePPIS Due Certificate 0.00 0.00 0.000.00 0.00 0.00 7,262,393.78 ) (1,731.01 0.000.000.00 ) (1,731.01 656,618.43 0.00 656,618.43 0.000.000.000.000.000.00 656,618.43 7,919,012.21 7,917,281.20 1,597,857,327.88 91 656,618.43 0.00 0 0.000.00 0 0.00 0 1,597,200,709.45 91 0.00 0.00 0.00 0.00 0.00 0.00 66,434.63 0.000.000.00 66,434.63 0.000.000.000.000.000.00 0.00 ) (66,434.63 7,260,662.77 Interest Not Advanced ( Current Period ) 0.00 0.00 Workout FeesLiquidation Fees 0.000.00 Less Non Recovered 0.00 0.000.00 0.00 0.00 Advance Summary (Advance Made by Servicer) 0 Page 7 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Statement Date: Cash Reconciliation Summary Group I Loans Current Scheduled Interest Interest Summary Less Deferred Interest Plus Gross Advance Interest Less PPIS Reducing Scheduled Int 5,727,851.98 0.000.00 Less ASER Interest Adv Reduction 0.00 Less Other Adjustment 0.00 Total 5,727,851.98 Unscheduled Interest:Prepayment Penalties 0.00 Yield Maintenance Penalties 0.00 Other Interest Proceeds 0.00 Total 0.00 Less Fees & Expenses Paid By/To Servicer Less Fee Paid To Servicer Less Fee Strips Paid by Servicer Special Servicing Fees Interest Due Serv on Advances Recoup of Prior Advances Misc. Fees & Expenses Total Unscheduled Fees & ExpensesTotal Interest Due Trust Less Fees & Expenses Paid By/To TrustTrustee FeeFee StripsMisc. FeesInterest Reserve Withholding Plus Interest Reserve DepositTotal Total Interest Due Certs Principal Summary Scheduled Principal:Current Scheduled PrincipalAdvanced Scheduled PrincipalScheduled PrincipalUnscheduled Principal:CurtailmentsPrepayments in FullLiquidation ProceedsRepurchase ProceedsOther Principal ProceedsTotal Unscheduled Principal Remittance Principal Remittance P&I Due Trust Remittance P&I Due Certs Pool Balance Summary Beginning PoolScheduled PrincipalUnscheduled PrincipalDeferred InterestLiquidationsRepurchases Ending Pool Balance Count Principal Interest Prior OutstandingPlus Current PeriodLess Recovered Ending Outstanding Servicing Fee Summary Current Servicing FeesPlus Fees Advanced for PPISLess Reduction for PPISPlus Delinquent Servicing Fees Total Servicing Fees PPIS Summary Gross PPISReduced by PPIEReduced by Shortfalls in FeesReduced by Other Amounts PPIS Reducing ScheduledInterest PPIS Reducing Servicing FeePPIS Due Certificate 0.00 0.00 0.000.00 0.00 0.00 5,676,145.83 ) (1,357.80 0.000.000.00 ) (1,357.80 596,116.23 0.00 596,116.23 0.000.000.000.000.000.00 596,116.23 6,272,262.06 6,270,904.26 1,253,349,907.10 70 596,116.23 0.00 0 0.000.00 0 0.00 0 1,252,753,790.87 70 0.00 0.00 0.00 0.00 0.00 0.00 51,706.15 0.000.000.00 51,706.15 0.000.000.000.000.000.00 0.00 ) (51,706.15 5,674,788.03 Interest Not Advanced ( Current Period ) 0.00 0.00 Workout FeesLiquidation Fees 0.000.00 Less Non Recovered 0.00 0.000.00 0.00 0.00 Advance Summary (Advance Made by Servicer) 0 Page 8 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Statement Date: Cash Reconciliation Summary Group II Loans Current Scheduled Interest Interest Summary Less Deferred Interest Plus Gross Advance Interest Less PPIS Reducing Scheduled Int 1,600,976.44 0.000.00 Less ASER Interest Adv Reduction 0.00 Less Other Adjustment 0.00 Total 1,600,976.44 Unscheduled Interest:Prepayment Penalties 0.00 Yield Maintenance Penalties 0.00 Other Interest Proceeds 0.00 Total 0.00 Less Fees & Expenses Paid By/To Servicer Less Fee Paid To Servicer Less Fee Strips Paid by Servicer Special Servicing Fees Interest Due Serv on Advances Recoup of Prior Advances Misc. Fees & Expenses Total Unscheduled Fees & ExpensesTotal Interest Due Trust Less Fees & Expenses Paid By/To TrustTrustee FeeFee StripsMisc. FeesInterest Reserve Withholding Plus Interest Reserve DepositTotal Total Interest Due Certs Principal Summary Scheduled Principal:Current Scheduled PrincipalAdvanced Scheduled PrincipalScheduled PrincipalUnscheduled Principal:CurtailmentsPrepayments in FullLiquidation ProceedsRepurchase ProceedsOther Principal ProceedsTotal Unscheduled Principal Remittance Principal Remittance P&I Due Trust Remittance P&I Due Certs Pool Balance Summary Beginning PoolScheduled PrincipalUnscheduled PrincipalDeferred InterestLiquidationsRepurchases Ending Pool Balance Count Principal Interest Prior OutstandingPlus Current PeriodLess Recovered Ending Outstanding Servicing Fee Summary Current Servicing FeesPlus Fees Advanced for PPISLess Reduction for PPISPlus Delinquent Servicing Fees Total Servicing Fees PPIS Summary Gross PPISReduced by PPIEReduced by Shortfalls in FeesReduced by Other Amounts PPIS Reducing ScheduledInterest PPIS Reducing Servicing FeePPIS Due Certificate 0.00 0.00 0.000.00 0.00 0.00 1,586,247.96 ) (373.22 0.000.000.00 ) (373.22 60,502.20 0.00 60,502.20 0.000.000.000.000.000.00 60,502.20 1,646,750.16 1,646,376.94 344,507,420.78 21 60,502.20 0.00 0 0.000.00 0 0.00 0 344,446,918.58 21 0.00 0.00 0.00 0.00 0.00 0.00 14,728.48 0.000.000.00 14,728.48 0.000.000.000.000.000.00 0.00 ) (14,728.48 1,585,874.74 Interest Not Advanced ( Current Period ) 0.00 0.00 Workout FeesLiquidation Fees 0.000.00 Less Non Recovered 0.00 0.000.00 0.00 0.00 Advance Summary (Advance Made by Servicer) 0 Page 9 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Class Accrued Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Bond Interest Reconciliation Deductions Allocable Deferred & Prior Prepay- Other Additions Interest Credit Support Original Current(4) Accrual Int. Short- falls Due ment Interest Int erest (2) Payment Amount PPIS Int erest Certificate Accretion Interest Loss/Exp Interest Penalties Proceeds (1) Interest Shortfalls Certificate Rate Pass Thru Method Days Outstanding Remaining Statement Date: Distributable Current Period (Shortfall)/ Recovery Int Accrual on Prior Shortfall (3) 3.001.00 0.00 0.00 0.00 0.00 0.00 A-1 30 214,608.00 214,608.00 214,608.00 0.00 30.00% 30.01% 30/360 4.208000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-1A 30 1,324,916.50 1,324,916.50 1,324,916.50 0.00 30.00% 30.01% 30/360 4.615000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-2 30 1,117,750.00 1,117,750.00 1,117,750.00 0.00 30.00% 30.01% 30/360 4.471000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-3 30 708,306.17 708,306.17 708,306.17 0.00 30.00% 30.01% 30/360 4.538000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-4 30 262,128.25 262,128.25 262,128.25 0.00 30.00% 30.01% 30/360 4.619000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-5 30 616,062.43 616,062.43 616,062.43 0.00 30.00% 30.01% 30/360 4.697000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 X-1 30 127,541.95 127,541.95 127,541.95 0.00 NA NA 30/360 0.095784734% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 X-2 30 966,545.79 966,545.79 966,545.79 0.00 NA NA 30/360 0.778023552% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-M 30 633,014.91 633,014.91 633,014.91 0.00 20.00% 20.01% 30/360 4.754000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A-J 30 511,955.14 511,955.14 511,955.14 0.00 12.00% 12.00% 30/360 4.806000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B 30 139,664.12 139,664.12 139,664.12 0.00 9.88% 9.88% 30/360 4.936000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 C 30 49,813.49 49,813.49 49,813.49 0.00 9.13% 9.13% 30/360 4.988000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 D 30 101,005.15 101,005.15 101,005.15 0.00 7.63% 7.63% 30/360 5.057000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 E 30 68,643.12 68,643.12 68,643.12 0.00 6.63% 6.63% 30/360 5.155000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 F 30 64,444.60 64,444.60 64,444.60 0.00 5.63% 5.63% 30/360 4.840000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 G 30 65,473.95 65,473.95 65,473.95 0.00 4.63% 4.63% 30/360 4.917000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 H 30 87,681.47 87,681.47 87,681.47 0.00 3.38% 3.38% 30/360 5.268000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 J 30 22,345.17 22,345.17 22,345.17 0.00 3.00% 3.00% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 K 30 22,345.17 22,345.17 22,345.17 0.00 2.63% 2.63% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 L 30 29,792.31 29,792.31 29,792.31 0.00 2.13% 2.13% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 M 30 14,898.02 14,898.02 14,898.02 0.00 1.88% 1.88% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 N 30 14,898.02 14,898.02 14,898.02 0.00 1.63% 1.63% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 O 30 14,894.29 14,894.29 14,894.29 0.00 1.38% 1.38% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 P 30 81,934.74 81,934.74 81,934.74 0.00 0.00% 0.00% 30/360 4.475000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Q 30 0.00 0.00 0.00 0.00 NA NA 30/360 0.000000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 W 30 0.00 0.00 0.00 0.00 NA NA 30/360 0.000000000% 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7,260,662.76 7,260,662.76 7,260,662.76 0.00 0.00 0.00 0.00 (2) Accrued - Deductions + Additions Interest (3) Includes interest accrued on outstanding Interest Shortfalls and/or Loss Allocations. Where applicable. 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 10 of 34 (1) Other Interest Proceeds are additional interest amounts specifically allocated to the bond(s) and used in determining the bonds Distributable Interest. (4) Determined as follows: (A) the ending balance of all the classes less (B) the sum of (i) the ending balance of the class and (ii) the ending balance of all classes which are not subordinate to the class divided by (A). GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Interest Adjustments Summary Statement Date: 0.00 0.00 0.00 0.00 Special Servicing Fees Workout Fees Liquidation Fees Legal Fees 0.00 0.00 Misc. Fees & Expenses Paid by/to Servicer Interest Paid to Servicer on Outstanding Advances 0.00 0.00 ASER Interest Advance Reduction Interest Not Advanced (Current Period) Recoup of Prior Advances by Servicer 0.00 0.00 Servicing Fees Paid Servicer on Loans Not Advanced Misc. Fees & Expenses Paid by Trust 0.00 0.00 0.00 Shortfall Due to Rate Modification Total Shortfall Allocated to the Bonds Total Interest Adjustment to the Bonds 0.00 Shortfall Allocated to the Bonds: Excess Allocated to the Bonds: Other Interest Proceeds Due the Bonds Yield Maintenance Penalties Due the Bonds Prepayment Penalties Due the Bonds Recovered ASER Interest Due the Bonds Recovered Interest Due the Bonds Less Total Shortfall Allocated to the Bonds Total Excess Allocated to the Bonds 0.00 0.00 Total Excess Allocated to the Bonds 0.00 0.00 Aggregate Interest Adjustment Allocated to the Bonds 0.00 0.00 0.00 0.00 Prepayment Interest Excess Due the Bonds 0.00 ARD Excess Interest 0.00 0.00 0.00 Net Prepayment Int. Shortfalls Allocated to the Bonds Other Interest Loss Interest Income 0.00 Page 11 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Rating Information Class CUSIP Fitch Moody's S&P Fitch Moody's S&P Original Ratings Rating Change/Change Date(1) Statement Date: A-1 361849M41 AAA NR AAA A-1A 361849M58 AAA NR AAA A-2 361849M66 AAA NR AAA A-3 361849M74 AAA NR AAA A-4 361849M82 AAA NR AAA A-5 361849Q21 AAA NR AAA X-1 361849N65 AAA NR AAA X-2 361849M90 AAA NR AAA A-M 361849Q39 AAA NR AAA A-J 361849N24 AAA NR AAA B 361849N32 AA NR AA C 361849N40 AA- NR AA- D 361849N57 A NR A E 361849N73 A- NR A- F 361849N81 BBB+ NR BBB+ G 361849N99 BBB NR BBB H 361849P22 BBB- NR BBB- J 361849P30 BB+ NR BB+ K 361849P48 BB NR BB L 361849P55 BB- NR BB- M 361849P63 B+ NR B+ N 361849P71 B NR B Page 12 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. NR - Designates that the class was not rated by the rating agency. (1) Changed ratings provided on this report are based on information provided by the applicable rating agency via electronic transmission. It shall be understood that this transmission will generally have been provided to LaSalle within 30 days of the payment date listed on this statement. Because ratings may have changed during the 30 day window, or may not be being provided by the rating agency in an electronic format and therefore notbeing updated on this report, LaSalle recommends that investors obtain current rating information directly from the rating agency. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Rating Information Class CUSIP Fitch Moody's S&P Fitch Moody's S&P Original Ratings Rating Change/Change Date(1) Statement Date: O 361849P89 B- NR B- P 361849P97 NR NR NR Q 111322608 NR NR NR W 111322616 NR NR NR Page 13 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. NR - Designates that the class was not rated by the rating agency. (1) Changed ratings provided on this report are based on information provided by the applicable rating agency via electronic transmission. It shall be understood that this transmission will generally have been provided to LaSalle within 30 days of the payment date listed on this statement. Because ratings may have changed during the 30 day window, or may not be being provided by the rating agency in an electronic format and therefore notbeing updated on this report, LaSalle recommends that investors obtain current rating information directly from the rating agency. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Distribution Date Delinq 1 Month Delinq 2 Months Delinq 3+ Months Foreclosure REO Modifications Specially Serviced Bankruptcy # Balance # Balance # Balance # Balance # Balance # Balance # Balance # Balance Delinquency Aging Categories Special Event Categories (1) Statement Date: ABN AMRO Acct: 722718.1 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 11-Jul-05 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category Page 14 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Distribution Date Delinq 1 Month Delinq 2 Months Delinq 3+ Months Foreclosure REO Modifications Specially Serviced Bankruptcy # Balance # Balance # Balance # Balance # Balance # Balance # Balance # Balance Delinquency Aging Categories Special Event Categories (1) Statement Date: Group I Loans ABN AMRO Acct: 722718.1 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 11-Jul-05 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category Page 15 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 Asset-Backed Facts ~ 15 Month Historical Loan Status Summary Distribution Date Delinq 1 Month Delinq 2 Months Delinq 3+ Months Foreclosure REO Modifications Specially Serviced Bankruptcy # Balance # Balance # Balance # Balance # Balance # Balance # Balance # Balance Delinquency Aging Categories Special Event Categories (1) Statement Date: Group II Loans ABN AMRO Acct: 722718.1 0.00% 0.00% 0.00% 0.00% 0 0.00% 0 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 11-Jul-05 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category Page 16 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary Distribution Date Ending Pool (1) Payoffs(2) Penalties Appraisal Reduct. (2) Liquidations (2) Realized Losses (2) Remaining Term Curr Weighted Avg. # Balance # Balance # Amount # Balance # Balance # Amount Life Coupon Remit Statement Date: Amort ABN AMRO Acct: 722718.1 Series 2005-C1 11-Jul-05 91 100.00% 1,597,200,709 99.96% 0.00% 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 94 242 5.50% 5.45% 0 0 0 0 (1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period. Page 17 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary Distribution Date Ending Pool (1) Payoffs(2) Penalties Appraisal Reduct. (2) Liquidations (2) Realized Losses (2) Remaining Term Curr Weighted Avg. # Balance # Balance # Amount # Balance # Balance # Amount Life Coupon Remit Statement Date: Group I Loans Amort ABN AMRO Acct: 722718.1 Series 2005-C1 11-Jul-05 70 76.92% 1,252,753,791 78.40% 0.00% 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 95 247 5.48% 5.43% 0 0 0 0 (1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period. Page 18 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary Distribution Date Ending Pool (1) Payoffs(2) Penalties Appraisal Reduct. (2) Liquidations (2) Realized Losses (2) Remaining Term Curr Weighted Avg. # Balance # Balance # Amount # Balance # Balance # Amount Life Coupon Remit Statement Date: Group II Loans Amort ABN AMRO Acct: 722718.1 Series 2005-C1 11-Jul-05 21 23.08% 344,446,919 21.56% 0.00% 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 89 225 5.58% 5.52% 0 0 0 0 (1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period. Page 19 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. GMAC Commercial Mortgage Securities, Inc. Mortgage Loan Characteristics ABN AMRO Acct: 722718.1 Series 2005-C1 Mortgage Pass-Through Certificates 30-Jun-05 10-Aug-05 N/A 11-Jul-05 11-Jul-05 Record Date: Next Payment: Prior Payment: Payment Date: Statement Date: Distribution of Mortgage Interest Rates Distribution of Principal Balances Distribution of Remaining Term (Balloon) Distribution of Remaining Term (Fully Amortizing) 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 20 of 34 Current Scheduled Balance # of Loans Scheduled Balance % of Balance Weighted Average Term Coupon PFY DSCR 1 797,541 0.05 117 5.88 0.00 % 0 to 2,000,000 % 4 9,784,965 0.61 151 5.51 0.00 % 2,000,000 to 3,000,000 % 12 43,145,382 2.70 116 5.59 0.00 % 3,000,000 to 4,000,000 % 10 48,469,952 3.03 126 5.49 0.00 % 4,000,000 to 6,000,000 % 13 91,452,229 5.73 109 5.40 0.00 % 6,000,000 to 8,000,000 % 6 53,868,057 3.37 108 5.52 0.00 % 8,000,000 to 10,000,000 % 18 222,672,262 13.94 115 5.45 0.00 % 10,000,000 to 15,000,000 % 19 416,388,075 26.07 107 5.54 0.00 % 15,000,000 to 30,000,000 % 1 44,350,914 2.78 117 5.19 0.00 % 30,000,000 to 50,000,000 % 7 666,271,332 41.71 70 5.53 0.00 % 50,000,000 & Above % 180,000,000 797,541 1,597,200,709 91 100.00 % Average Schedule BalanceMaximum Schedule BalanceMinimum Schedule Balance 17,551,656 Current Mortgage Interest Rate # of Loans Scheduled Balance % of Balance Weighted Average Term Coupon PFY DSCR 2 44,658,860 2.80 117 4.85 0.00 % 0.100% % to 4.999% 11 310,582,902 19.45 75 5.13 0.00 % 5.000% % to 5.249% 40 698,992,326 43.76 104 5.40 0.00 % 5.250% % to 5.499% 21 270,640,582 16.94 84 5.63 0.00 % 5.500% % to 5.749% 13 134,523,805 8.42 110 5.86 0.00 % 5.750% % to 5.999% 2 97,266,040 6.09 72 6.42 0.00 % 6.000% % to 6.499% 2 40,536,195 2.54 118 6.71 0.00 % 6.500% % & Above 91 1,597,200,709 Minimum Mortgage Interest RateMaximum Mortgage Interest Rate 100.00 % 4.766%6.720% Fully Amortizing Mortgage Loans # of Loans Scheduled Balance % of Balance Weighted Average Term Coupon PFY DSCR 0 0 0.00 0 0.00 0.00 % % to 0 75 0 0 0.00 0 0.00 0.00 % % to 76 150 0 0 0.00 0 0.00 0.00 % % to 151 225 3 11,060,938 0.69 236 5.86 0.00 % % to 226 300 0 0 0.00 0 0.00 0.00 % % & 301 Above 239 235 3 11,060,938 Minimum Remaining TermMaximum Remaining Term 0.69 % Balloon Mortgage Loans # of Loans Scheduled Balance % of Balance Weighted Average Term Coupon PFY DSCR 0 0 0.00 0 0.00 0.00 % % 0 to 20 0 0 0.00 0 0.00 0.00 % % 21 to 40 13 567,285,783 35.52 57 5.41 0.00 % % 41 to 60 2 100,265,332 6.28 65 6.35 0.00 % % 61 to 80 1 4,500,000 0.28 94 5.30 0.00 % % 81 to 100 70 877,348,487 54.93 117 5.45 0.00 % % 101 to 120 0 0 0.00 0 0.00 0.00 % % 121 to 140 2 36,740,169 2.30 163 5.68 0.00 % % 141 & Above 173 51 88 1,586,139,771 Minimum Remaining TermMaximum Remaining Term % 99.31 GMAC Commercial Mortgage Securities, Inc. Mortgage Loan Characteristics ABN AMRO Acct: 722718.1 Series 2005-C1 Mortgage Pass-Through Certificates 30-Jun-05 10-Aug-05 N/A 11-Jul-05 11-Jul-05 Record Date: Next Payment: Prior Payment: Payment Date: Statement Date: Geographic Distribution Distribution of DSCR (PFY) Distribution of DSCR (Cutoff) 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 21 of 34 Debt Service Coverage Ratio # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR 0 0 0.00 0 0.00 0.00 % % 0.010 1.090 0 0 0.00 0 0.00 0.00 % % 1.100 1.190 0 0 0.00 0 0.00 0.00 % % 1.200 1.290 0 0 0.00 0 0.00 0.00 % % 1.300 1.390 0 0 0.00 0 0.00 0.00 % % 1.400 1.490 0 0 0.00 0 0.00 0.00 % % 1.500 1.590 0 0 0.00 0 0.00 0.00 % % 1.600 1.690 0 0 0.00 0 0.00 0.00 % % 1.700 1.790 0 0 0.00 0 0.00 0.00 % % 1.800 1.890 0 0 0.00 0 0.00 0.00 % % 1.900 1.990 0 0 0.00 0 0.00 0.00 % % 2.000 & Above 91 1,597,200,709 100.00 94 5.50 0.00 % % Unknown 0.0000.000 91 1,597,200,709 100.00 % Minimum DSCR Maximum DSCR Debt Service Coverage Ratio # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR 0 0 0.00 0 0.00 0.00 % % 0.010 1.000 1 2,793,853 0.17 239 5.88 0.00 % % 1.001 1.100 5 24,776,695 1.55 136 5.54 0.00 % % 1.101 1.200 38 635,021,737 39.76 104 5.51 0.00 % % 1.201 1.300 22 328,354,953 20.56 100 5.76 0.00 % % 1.301 1.400 6 85,042,432 5.32 81 5.62 0.00 % % 1.401 1.500 8 228,736,252 14.32 75 5.47 0.00 % % 1.501 1.600 3 43,348,380 2.71 123 5.55 0.00 % % 1.601 1.700 1 5,089,091 0.32 118 5.28 0.00 % % 1.701 1.800 2 7,530,915 0.47 118 5.40 0.00 % % 1.801 1.900 1 3,800,000 0.24 116 5.24 0.00 % % 1.901 2.000 0 0 0.00 0 0.00 0.00 % % 2.001 2.100 1 27,000,000 1.69 114 5.30 0.00 % % 2.101 2.200 2 25,706,402 1.61 117 4.80 0.00 % % 2.201 2.300 1 180,000,000 11.27 55 5.13 0.00 % % 2.301 & Above 2.380 1.050 91 1,597,200,709 100.00 Minimum DSCR Maximum DSCR % Geographic Location # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR New York 4 289,116,819 18.10 57 5.32 0.00 % % California 12 194,491,695 12.18 95 5.55 0.00 % % New Jersey 8 168,682,621 10.56 111 5.47 0.00 % % Texas 10 134,899,566 8.45 113 5.75 0.00 % % Undefined 3 106,679,782 6.68 70 6.36 0.00 % % Nevada 3 77,618,294 4.86 73 5.48 0.00 % % Michigan 5 77,216,743 4.83 93 5.50 0.00 % % Florida 5 75,862,006 4.75 106 5.18 0.00 % % Connecticut 4 63,300,000 3.96 116 5.49 0.00 % % Arkansas 5 57,001,404 3.57 124 5.44 0.00 % % Missouri 1 44,350,914 2.78 117 5.19 0.00 % % North Carolina 3 38,250,000 2.39 116 5.14 0.00 % % Colorado 4 36,382,829 2.28 109 5.39 0.00 % % Georgia 3 33,144,906 2.08 117 5.42 0.00 % % Maryland 2 31,212,631 1.95 70 5.59 0.00 % % District of Columbia 1 27,000,000 1.69 114 5.30 0.00 % % Pennsylvania 1 24,918,087 1.56 117 5.30 0.00 % % Virginia 3 23,425,765 1.47 115 5.35 0.00 % % Arizona 2 20,540,650 1.29 66 5.92 0.00 % % Washington 2 15,966,378 1.00 147 5.39 0.00 % % Illinois 1 12,400,000 0.78 119 5.27 0.00 % % New Hampshire 1 10,999,252 0.69 117 5.43 0.00 % % Utah 1 7,080,000 0.44 51 5.14 0.00 % % Oregon 2 6,886,285 0.43 101 5.31 0.00 % % Kentucky 1 4,500,707 0.28 235 6.08 0.00 % % Delaware 1 4,390,265 0.27 118 5.12 0.00 % % Alabama 1 3,792,800 0.24 118 5.84 0.00 % % Mississippi 1 3,700,000 0.23 58 5.58 0.00 % % West Virginia 1 3,390,309 0.21 118 5.74 0.00 % % 100.00 1,597,200,709 91 % GMAC Commercial Mortgage Securities, Inc. Mortgage Loan Characteristics ABN AMRO Acct: 722718.1 Series 2005-C1 Mortgage Pass-Through Certificates 30-Jun-05 10-Aug-05 N/A 11-Jul-05 11-Jul-05 Record Date: Next Payment: Prior Payment: Payment Date: Statement Date: Distribution of Loan Seasoning Distribution of Property Types Distribution of Year Loans Maturing Distribution of Amortization Type 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 22 of 34 Property Types # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR Office 21 660,092,271 41.33 86 5.40 0.00 % % Multifamily 21 344,446,919 21.57 89 5.58 0.00 % % Retail 27 245,734,218 15.39 118 5.45 0.00 % % Lodging 4 148,643,808 9.31 82 5.93 0.00 % % Industrial 9 93,882,719 5.88 123 5.38 0.00 % % Other 2 47,986,168 3.00 83 5.66 0.00 % % Self storage 4 24,134,607 1.51 116 5.75 0.00 % % Mixed use 2 17,880,000 1.12 90 5.27 0.00 % % Mobile home park 1 14,400,000 0.90 119 5.17 0.00 % % 1,597,200,709 91 100.00 % Amortization Type # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR Amortizing/IO 1 24,878,765 1.56 173 5.84 0.00 % % AmortizingBalloon 46 508,005,006 31.81 104 5.74 0.00 % % Full Amortizing 3 11,060,938 0.69 236 5.86 0.00 % % IO Maturity Balloon 6 465,550,000 29.15 57 5.38 0.00 % % IO/Amortizing 35 587,706,000 36.80 109 5.38 0.00 % % 1,597,200,709 91 100.00 % Number of Months # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR 16 255,612,404 16.00 97 0.00 % % 5.46 0 to 1 22 350,418,061 21.94 89 0.00 % % 5.88 2 to 2 19 364,665,582 22.83 107 0.00 % % 5.41 3 to 3 10 231,087,295 14.47 91 0.00 % % 5.45 4 to 4 12 260,791,085 16.33 71 0.00 % % 5.21 5 to 5 6 76,927,779 4.82 108 0.00 % % 5.44 6 to 6 4 47,069,557 2.95 143 0.00 % % 5.77 7 to 7 1 3,548,945 0.22 112 0.00 % % 5.45 8 to 8 1 7,080,000 0.44 51 0.00 % % 5.14 9 to 9 0 0 0.00 0 0.00 % % 0.00 10 to 10 0 0 0.00 0 0.00 % % 0.00 11 or More 91 1,597,200,709 100.00 % Year # of Loans Scheduled Balance % of Balance WAMM WAC PFY DSCR 0 0 0.00 0 0.00 0.00 % % 2005 0 0 0.00 0 0.00 0.00 % % 2006 0 0 0.00 0 0.00 0.00 % % 2007 0 0 0.00 0 0.00 0.00 % % 2008 1 7,080,000 0.44 51 5.14 0.00 % % 2009 13 652,971,116 40.88 58 5.56 0.00 % % 2010 0 0 0.00 0 0.00 0.00 % % 2011 1 7,500,000 0.47 80 5.30 0.00 % % 2012 1 4,500,000 0.28 94 5.30 0.00 % % 2013 3 21,239,738 1.33 113 5.73 0.00 % % 2014 67 856,108,749 53.60 117 5.45 0.00 % % 2015 5 47,801,107 2.99 180 5.72 0.00 % % 2016 & Greater 100.00 1,597,200,709 91 % GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Delinquent Loan Detail Disclosure Control # PaidThruDate Current P&I Advance Outst anding P& I Advances** Out. Property ProtectionAdvances Loan Status Code (1) Special Servicer Transfer Date Foreclosure Date Bankruptcy Date REO Date Statement Date: Total 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 23 of 34 A. In Grace Period 1. Delinq. 1 month 2. Delinq. 2 months 3. Delinquent 3 + months 4. Performing Matured Balloon ** Outstanding P&I Advances include the current period P&I Advances and may include Servicer and Trust Advances. 7. Foreclosure 9. REO B. Late Payment but < 1 month delinq. 5. Non Performing Matured Balloon GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Historical Collateral Level Prepayment Report Disclosure Control # Payoff Period Initial Balance Type Payoff Amount Penalty Amount Prepayment Date Maturity Date Property Type Geographic Location Statement Date: Cumulative Current 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 24 of 34 GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Loan Level Detail Disclosure Control # Group Property Type Maturity Date PFY DSCR OperatingStatement Date Geo. Location Ending Principal Balance NoteRate Scheduled P&I Prepayment Amount Prepayment Date Loan Status Code (1) Statement Date: NY 5.13% 1-Feb-10 GMAC5C1A Office 0.00 180,000,000 769,189 1 NY 5.63% 1-Mar-10 GMAC5C1A Office 0.00 100,000,000 469,216 2 CA 5.46% 8-Jun-10 GMAC5C1B Multifamily 0.00 100,000,000 455,000 3 VV 6.44% 1-Nov-10 GMAC5C1A Lodging 0.00 92,765,332 624,460 4 NJ 5.49% 1-Apr-15 GMAC5C1A Office 0.00 79,686,000 364,563 5 NV 5.44% 1-May-10 GMAC5C1A Office 0.00 57,750,000 261,800 6 TX 5.38% 1-Mar-15 GMAC5C1A Office 0.00 56,070,000 251,381 7 MO 5.19% 1-Apr-15 GMAC5C1A Office 0.00 44,350,914 244,080 8 NJ 5.26% 1-Apr-15 GMAC5C1A Industrial 0.00 21,500,000 94,242 9 NJ 5.26% 1-Apr-15 GMAC5C1A Industrial 0.00 20,500,000 89,858 10 DC 5.30% 1-Jan-15 GMAC5C1A Lodging 0.00 27,000,000 119,250 11 MI 5.84% 1-Apr-10 GMAC5C1A Other 0.00 26,386,168 168,157 12 PA 5.30% 1-Apr-15 GMAC5C1A Retail 0.00 24,918,087 138,826 13 FL 4.77% 1-Apr-15 GMAC5C1A Lodging 0.00 24,908,860 130,653 14 CA 5.84% 1-Dec-19 GMAC5C1A Office 0.00 24,878,765 138,955 15 MD 5.62% 1-Apr-10 GMAC5C1B Multifamily 0.00 24,500,000 114,742 16 NJ 5.71% 1-May-10 GMAC5C1B Multifamily 0.00 24,000,000 114,200 17 FL 5.47% 1-Jun-15 GMAC5C1B Multifamily 0.00 23,000,000 104,842 18 CT 5.45% 1-Jan-15 GMAC5C1A Other 0.00 21,600,000 98,100 19 TX 6.72% 1-May-15 GMAC5C1B Multifamily 0.00 21,366,504 137,368 20 MI 5.11% 1-Apr-15 GMAC5C1B Multifamily 0.00 21,250,000 90,490 21 CO 5.35% 8-Apr-15 GMAC5C1A Retail 0.00 20,760,000 92,555 22 NC 4.96% 1-Mar-15 GMAC5C1B Multifamily 0.00 19,750,000 81,633 23 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 25 of 34 * NOI and DSCR, if available and reportable under the terms of the trust agreement, are based on information obtained from the related borrower, and no other party to the agreement shall be held liable for the accuracy or methodology used to determine such figures. (1) Legend: A. In Grace Period B. Late Payment but < 1 month delinq 1. Delinquent 1 month2. Delinquent 2 months 3. Delinquent 3+ months 4. Performing Matured Balloon 7. Foreclosure 9. REO 5. Non Performing Matured Ballon GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Loan Level Detail Disclosure Control # Group Property Type Maturity Date PFY DSCR OperatingStatement Date Geo. Location Ending Principal Balance NoteRate Scheduled P&I Prepayment Amount Prepayment Date Loan Status Code (1) Statement Date: TX 6.69% 1-May-15 GMAC5C1B Multifamily 0.00 19,169,691 122,765 24 CT 5.35% 1-Mar-15 GMAC5C1A Retail 0.00 17,500,000 78,021 25 AZ 5.95% 1-Apr-10 GMAC5C1A Office 0.00 17,400,000 86,275 26 GA 5.43% 1-May-15 GMAC5C1A Retail 0.00 16,000,000 72,400 27 AR 5.32% 1-Jun-15 GMAC5C1A Industrial 0.00 14,880,000 65,906 28 FL 5.01% 1-Feb-10 GMAC5C1A Retail 0.00 14,500,000 60,538 29 MI 5.17% 1-Jun-15 GMAC5C1A Mobile home park 0.00 14,400,000 62,040 30 AR 5.62% 1-Jun-15 GMAC5C1A Retail 0.00 14,000,000 65,567 31 CA 5.45% 1-May-15 GMAC5C1A Office 0.00 13,971,122 79,052 32 NC 5.35% 1-Feb-15 GMAC5C1B Multifamily 0.00 13,600,000 60,633 33 CT 5.47% 1-May-15 GMAC5C1B Multifamily 0.00 13,500,000 61,549 34 IL 5.27% 1-Jun-15 GMAC5C1A Office 0.00 12,400,000 54,457 35 WA 5.33% 1-Jun-15 GMAC5C1B Multifamily 0.00 12,200,000 54,188 36 CA 5.84% 1-Apr-15 GMAC5C1A Office 0.00 12,164,239 71,895 37 AR 5.35% 1-Apr-17 GMAC5C1A Retail 0.00 11,861,404 66,451 38 MI 5.80% 1-Jan-15 GMAC5C1B Multifamily 0.00 11,210,960 66,188 39 NH 5.43% 1-Apr-15 GMAC5C1A Retail 0.00 10,999,252 67,396 40 NV 5.54% 1-May-15 GMAC5C1A Office 0.00 10,977,746 62,733 41 VA 5.35% 1-Mar-15 GMAC5C1A Mixed use 0.00 10,800,000 48,150 42 CT 5.84% 1-Jun-15 GMAC5C1A Retail 0.00 10,700,000 52,073 43 VV 5.96% 1-Dec-14 GMAC5C1A Self storage 0.00 10,365,505 67,203 44 VA 5.35% 1-Feb-15 GMAC5C1A Industrial 0.00 10,142,035 56,958 45 GA 5.49% 1-Feb-15 GMAC5C1A Retail 0.00 9,894,906 56,433 46 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 26 of 34 * NOI and DSCR, if available and reportable under the terms of the trust agreement, are based on information obtained from the related borrower, and no other party to the agreement shall be held liable for the accuracy or methodology used to determine such figures. (1) Legend: A. In Grace Period B. Late Payment but < 1 month delinq 1. Delinquent 1 month2. Delinquent 2 months 3. Delinquent 3+ months 4. Performing Matured Balloon 7. Foreclosure 9. REO 5. Non Performing Matured Ballon GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Loan Level Detail Disclosure Control # Group Property Type Maturity Date PFY DSCR OperatingStatement Date Geo. Location Ending Principal Balance NoteRate Scheduled P&I Prepayment Amount Prepayment Date Loan Status Code (1) Statement Date: NJ 5.55% 1-May-15 GMAC5C1A Retail 0.00 9,630,519 55,095 47 CA 5.70% 1-Feb-15 GMAC5C1A Retail 0.00 8,952,083 52,236 48 NV 5.66% 1-Jun-15 GMAC5C1A Retail 0.00 8,890,548 51,430 49 AR 5.62% 1-Jun-15 GMAC5C1A Retail 0.00 8,500,000 39,808 50 TX 5.06% 1-Jan-10 GMAC5C1B Multifamily 0.00 8,000,000 33,733 51 CA 5.37% 1-Jun-15 GMAC5C1A Retail 0.00 7,691,356 43,070 52 AR 5.32% 1-Jun-15 GMAC5C1A Industrial 0.00 7,760,000 34,370 53 CO 5.30% 1-Mar-12 GMAC5C1A Office 0.00 7,500,000 33,125 54 FL 5.50% 1-Mar-15 GMAC5C1A Office 0.00 7,329,821 41,789 55 CO 5.53% 1-Dec-14 GMAC5C1B Multifamily 0.00 7,325,288 42,042 56 GA 5.28% 1-May-15 GMAC5C1B Multifamily 0.00 7,250,000 31,900 57 CA 5.62% 1-Jun-15 GMAC5C1A Self storage 0.00 7,188,988 44,732 58 UT 5.14% 1-Oct-09 GMAC5C1A Mixed use 0.00 7,080,000 30,326 59 MD 5.49% 1-Jun-15 GMAC5C1A Office 0.00 6,712,631 38,113 60 TX 5.54% 1-Apr-15 GMAC5C1A Office 0.00 6,679,098 38,210 61 TX 5.24% 1-Feb-15 GMAC5C1A Office 0.00 6,561,723 36,405 62 TX 5.16% 1-Mar-15 GMAC5C1A Retail 0.00 6,250,000 26,875 63 FL 5.82% 1-May-15 GMAC5C1A Retail 0.00 6,123,325 36,075 64 NJ 5.63% 1-Apr-15 GMAC5C1A Industrial 0.00 5,483,158 31,678 65 TX 5.28% 1-May-15 GMAC5C1A Office 0.00 5,188,877 28,811 66 NY 5.66% 1-Jan-15 GMAC5C1A Industrial 0.00 5,152,825 32,431 67 NJ 5.28% 1-May-15 GMAC5C1A Retail 0.00 5,089,091 28,257 68 NC 5.32% 1-Apr-15 GMAC5C1A Retail 0.00 4,900,000 21,723 69 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 27 of 34 * NOI and DSCR, if available and reportable under the terms of the trust agreement, are based on information obtained from the related borrower, and no other party to the agreement shall be held liable for the accuracy or methodology used to determine such figures. (1) Legend: A. In Grace Period B. Late Payment but < 1 month delinq 1. Delinquent 1 month2. Delinquent 2 months 3. Delinquent 3+ months 4. Performing Matured Balloon 7. Foreclosure 9. REO 5. Non Performing Matured Ballon GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Loan Level Detail Disclosure Control # Group Property Type Maturity Date PFY DSCR OperatingStatement Date Geo. Location Ending Principal Balance NoteRate Scheduled P&I Prepayment Amount Prepayment Date Loan Status Code (1) Statement Date: CA 5.78% 1-May-15 GMAC5C1A Retail 0.00 4,770,000 22,976 70 KY 6.08% 1-Feb-25 GMAC5C1A Industrial 0.00 4,500,707 32,808 71 OR 5.30% 1-May-13 GMAC5C1B Multifamily 0.00 4,500,000 19,875 72 CA 5.45% 1-Jun-15 GMAC5C1A Office 0.00 4,495,028 25,410 73 DE 5.12% 1-May-15 GMAC5C1A Retail 0.00 4,390,265 23,944 74 MI 5.73% 1-Feb-10 GMAC5C1A Lodging 0.00 3,969,615 25,116 75 NY 5.71% 1-Jan-15 GMAC5C1A Industrial 0.00 3,963,994 25,068 76 CA 5.24% 1-Mar-15 GMAC5C1B Multifamily 0.00 3,800,000 16,593 77 AL 5.84% 1-May-15 GMAC5C1A Retail 0.00 3,792,800 22,394 78 WA 5.58% 1-Mar-25 GMAC5C1A Retail 0.00 3,766,378 26,312 79 MS 5.58% 1-May-10 GMAC5C1B Multifamily 0.00 3,700,000 17,205 80 KT 5.45% 1-Nov-14 GMAC5C1A Retail 0.00 3,548,945 20,215 81 TX 5.32% 1-May-15 GMAC5C1A Office 0.00 3,492,577 19,479 82 WV 5.74% 1-May-15 GMAC5C1A Retail 0.00 3,390,309 21,369 83 CA 5.41% 1-May-15 GMAC5C1A Self storage 0.00 3,339,903 20,392 84 CA 5.71% 1-Apr-15 GMAC5C1A Self storage 0.00 3,240,211 18,884 85 AZ 5.78% 1-Apr-15 GMAC5C1B Multifamily 0.00 3,140,650 18,443 86 NJ 5.88% 1-Jun-25 GMAC5C1A Retail 0.00 2,793,853 19,867 87 VA 5.35% 1-Feb-15 GMAC5C1A Office 0.00 2,483,730 14,369 88 OR 5.32% 1-Feb-15 GMAC5C1B Multifamily 0.00 2,386,285 13,357 89 TX 5.41% 1-Mar-15 GMAC5C1A Retail 0.00 2,121,096 11,974 90 CO 5.88% 1-Apr-15 GMAC5C1B Multifamily 0.00 797,541 4,732 91 1,597,200,709 7,985,447 0 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 28 of 34 * NOI and DSCR, if available and reportable under the terms of the trust agreement, are based on information obtained from the related borrower, and no other party to the agreement shall be held liable for the accuracy or methodology used to determine such figures. (1) Legend: A. In Grace Period B. Late Payment but < 1 month delinq 1. Delinquent 1 month2. Delinquent 2 months 3. Delinquent 3+ months 4. Performing Matured Balloon 7. Foreclosure 9. REO 5. Non Performing Matured Ballon GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Specially Serviced (Part I) ~ Loan Detail (End of Period) Disclosure Control # Servicing Xfer Date Balance Note Rate Maturity Date Remaining Property Type Geo. Location NOI DSCR NOIDate Schedule Actual Life Statement Date: Loan Status Code(1) 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 29 of 34 (1) Legend: A. P&I Adv - in Grace Period B. P&I Adv - < one month delinq 1. P&I Adv - delinquent 1 month 2. P&I Adv - delinquent 2 months 3. P&I Adv - delinquent 3+ months 4. Mat. Balloon/Assumed P&I 7. Foreclosure 9. REO 5. Non Performing Mat. Balloon GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Specially Serviced Loan Detail (Part II) ~ Servicer Comments (End of Period) Disclosure Control # Resolution Strategy Comments Statement Date: 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 30 of 34 GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 Historical Collateral Level REO Report Property Type Statement Date: State Actual Balance Scheduled Balance Recent Appraisal Value Appraisal Reduction Amount Date Liquidated Liquidation Proceeds Liquidation Expenses Realized Loss Disclosure Control # REO Date City Appraisal Date ABN AMRO Acct: 722718.1 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 31 of 34 GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Modified Loan Detail Disclosure Control # Modification Date Cutoff Maturity Date Modification Description Modified Maturity Date Statement Date: 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 32 of 34 GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Realized Loss Detail Period Disclosure Control # Appraisal Date Appraisal Value Beginning Scheduled Balance Gross Proceeds Gross Proceeds as a % of Sched. Balance Aggregate Liquidation Expenses * Net Liquidation Proceeds Net Proceeds as a % of Sched. Balance Realized Loss Statement Date: Current Total Cumulative 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A. Page 33 of 34 * Aggregate liquidation expenses also include outstanding P&I advances and unpaid servicing fees, unpaid trustee fees, etc.. GMAC Commercial Mortgage Securities, Inc. Payment Date:Prior Payment:Next Payment:Record Date: 11-Jul-0511-Jul-05 N/A 10-Aug-05 30-Jun-05 Mortgage Pass-Through Certificates Series 2005-C1 ABN AMRO Acct: 722718.1 Appraisal Reduction Detail Disclosure Control# Appraisal Red. Date Scheduled Balance ASER Note Rate Maturity Date Property Type Geographic Location Appraisal Value Date DSCR Statement Date: Remaining Term Life ARA Amount Current P&I Advance Page 34 of 34 08-Jul-2005 - 11:43 (W023-W052) (c) 2005 LaSalle Bank N.A.

GMAC Commercial Mortgage Securities, Inc.

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Reporting Package Table of Contents

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Administrator:
Ann Kelly 312.904.1487
ann.kelly@abnamro.com

Analyst:
Clifford Song 714.259.6244
Clifford.Song@abnamro.com

Statement Date:

135 S. LaSalle Street, Suite 1625
Chicago, IL 60603
USA

Statements to Certificateholders
Cash Reconciliation Summary
Bond Interest Reconciliation
Shortfall Summary Report

Rating Information

Asset-Backed Facts ~ 15 Month Loan Status Summary
Asset-Backed Facts ~ 15 Month Loan Payoff/Loss Summary

Mortgage Loan Characteristics
Delinquent Loan Detail
Historical Collateral Prepayment

Page 2-5
Page 6-8
Page 9
Page 10

Page 11-12

Page 13-15
Page 16-18

Page 19-21
Page 22

Page 23

Loan Level Detail

Specially Serviced (Part I) - Loan Detail
Specially Serviced (Part II) - Servicer Comments
Historical REO Report

Modified Loan Detail
Realized Loss Detail
Appraisal Reduction Detail

Page 24-27

Page 28
Page 29
Page 30

Page 31
Page 32
Page 33

Page(s)

Information is available for this issue from the following sources

Issue Id:

Monthly Data File
Name:

GMAC05C1

GMAC05C1_200512_3.ZIP

Closing Date:

First Payment Date:

Rated Final Payment: Date:

16-Jun-05
11-Jul-05

11-May-43

Parties to The Transaction

Issuer: GMAC Commercial Mortgage Securities, Inc.

Depositor: GMAC Commercial Mortgage Securities, Inc.

Underwriter: Deutsche Bank Securities Inc./GMAC Commercial Holding Capital Markets Corp./Morgan Stanley & Co. Incorporated

Master Servicer: GMAC Commercial Mortgage Corporation

Special Servicer: GMAC Commercial Mortgage Corporation

Rating Agency: Standard & Poor's Ratings Services/Fitch Ratings

800.246.5761

LaSalle Factor Line

LaSalle Web Site

Servicer Web Site

www.gmaccm.com

www.etrustee.net

Page 1 of 33

Class

CUSIP

Original

Opening

Principal

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

WAC:
WAMM:

Payment Date:
Prior Payment:
Next Payment:
Record Date:

5.503548%

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

GMAC Commercial Mortgage Securities, Inc.

Mortgage Pass-Through Certificates

Series 2005-C1

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

REMIC III

Statement Date:

ABN AMRO Acct: 722718.1

954.275702941

10.118072712

0.000000000

944.157630229

3.346326797

Fixed

0.00

0.000000000

4.2080000000%

0.000000000

361849M41

A-1

61,200,000.00

619,226.05

0.00

57,782,446.97

204,795.20

58,401,673.02

999.214930582

0.179795795

0.000000000

999.035134787

3.842814079

Fixed

0.00

0.000000000

4.6150000000%

0.000000000

361849M58

A-1A

344,507,000.00

61,940.91

0.00

344,174,597.18

1,323,876.35

344,236,538.09

1000.000000000

0.000000000

1000.000000000

3.725833333

Fixed

0.00

0.000000000

4.4710000000%

0.000000000

361849M66

A-2

300,000,000.00

0.00

300,000,000.00

1,117,750.00

300,000,000.00

1000.000000000

0.000000000

1000.000000000

3.781666684

Fixed

0.00

0.000000000

4.5380000000%

0.000000000

361849M74

A-3

187,300,000.00

0.00

187,300,000.00

708,306.17

187,300,000.00

1000.000000000

0.000000000

1000.000000000

3.849166667

Fixed

0.00

0.000000000

4.6190000000%

0.000000000

361849M82

A-4

68,100,000.00

0.00

68,100,000.00

262,128.25

68,100,000.00

1000.000000000

0.000000000

1000.000000000

3.914166640

Fixed

0.00

0.000000000

4.6970000000%

0.000000000

361849Q21

A-5

157,393,000.00

0.00

157,393,000.00

616,062.43

157,393,000.00

998.079434979

0.000000000

997.653134741

0.080245575

0.00

0.000000000

0.0964799878%

0.000000000

361849N65

X-1

1,597,857,327.00

0.00

1,594,107,371.15

128,220.98

1,594,788,538.11

1000.000000000

0.000000000

1000.000000000

0.645436294

0.00

0.000000000

0.7745235519%

0.000000000

361849M90

X-2

1,490,771,000.00

0.00

1,490,771,000.00

962,197.71

1,490,771,000.00

1000.000000000

0.000000000

1000.000000000

3.961666677

Fixed

0.00

0.000000000

4.7540000000%

0.000000000

361849Q39

A-M

159,785,000.00

0.00

159,785,000.00

633,014.91

159,785,000.00

1000.000000000

0.000000000

1000.000000000

4.004999961

Fixed

0.00

0.000000000

4.8060000000%

0.000000000

361849N24

A-J

127,829,000.00

0.00

127,829,000.00

511,955.14

127,829,000.00

1000.000000000

0.000000000

1000.000000000

4.113333333

Fixed

0.00

0.000000000

4.9360000000%

0.000000000

361849N32

33,954,000.00

0.00

33,954,000.00

139,664.12

33,954,000.00

1000.000000000

0.000000000

1000.000000000

4.156666389

4.9880000000%

0.00

0.000000000

4.9880000000%

0.000000000

361849N40

11,984,000.00

0.00

11,984,000.00

49,813.49

11,984,000.00

1000.000000000

0.000000000

1000.000000000

4.214166806

5.0570000000%

0.00

0.000000000

5.0570000000%

0.000000000

361849N57

23,968,000.00

0.00

23,968,000.00

101,005.15

23,968,000.00

1000.000000000

0.000000000

1000.000000000

4.295833281

5.1550000000%

0.00

0.000000000

5.1550000000%

0.000000000

361849N73

15,979,000.00

0.00

15,979,000.00

68,643.12

15,979,000.00

1000.000000000

0.000000000

1000.000000000

4.033333333

4.8400000000%

0.00

0.000000000

4.8400000000%

0.000000000

361849N81

15,978,000.00

0.00

15,978,000.00

64,444.60

15,978,000.00

1000.000000000

0.000000000

1000.000000000

4.097499844

4.9170000000%

0.00

0.000000000

4.9170000000%

0.000000000

361849N99

15,979,000.00

0.00

15,979,000.00

65,473.95

15,979,000.00

1000.000000000

0.000000000

1000.000000000

4.390000000

5.2680000000%

0.00

0.000000000

5.2680000000%

0.000000000

361849P22

19,973,000.00

0.00

19,973,000.00

87,681.47

19,973,000.00

Page 2 of 33

Notes: (1) N denotes notional balance not included in total (2) Accrued Interest Plus/Minus Interest Adjustment Minus Deferred Interest equals Interest Payment (3) Estimated. * Denotes Controlling Class

Class

CUSIP

Original

Opening

Principal

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

WAC:
WAMM:

Payment Date:
Prior Payment:
Next Payment:
Record Date:

5.503548%

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

GMAC Commercial Mortgage Securities, Inc.

Mortgage Pass-Through Certificates

Series 2005-C1

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

REMIC III

Statement Date:

ABN AMRO Acct: 722718.1

1000.000000000

0.000000000

1000.000000000

3.729167223

4.4750000000%

0.00

0.000000000

4.4750000000%

0.000000000

361849P30

5,992,000.00

0.00

5,992,000.00

22,345.17

5,992,000.00

1000.000000000

0.000000000

1000.000000000

3.729167223

4.4750000000%

0.00

0.000000000

4.4750000000%

0.000000000

361849P48

5,992,000.00

0.00

5,992,000.00

22,345.17

5,992,000.00

1000.000000000

0.000000000

1000.000000000

3.729166354

4.4750000000%

0.00

0.000000000

4.4750000000%

0.000000000

361849P55

7,989,000.00

0.00

7,989,000.00

29,792.31

7,989,000.00

1000.000000000

0.000000000

1000.000000000

3.729166458

4.4750000000%

0.00

0.000000000

4.4750000000%

0.000000000

361849P63

3,995,000.00

0.00

3,995,000.00

14,898.02

3,995,000.00

1000.000000000

0.000000000

1000.000000000

3.729166458

4.4750000000%

0.00

0.000000000

4.4750000000%

0.000000000

361849P71

3,995,000.00

0.00

3,995,000.00

14,898.02

3,995,000.00

1000.000000000

0.000000000

1000.000000000

3.729166249

4.4750000000%

0.00

0.000000000

4.4750000000%

0.000000000

361849P89

3,994,000.00

0.00

3,994,000.00

14,894.29

3,994,000.00

1000.000000000

0.000000000

1000.000000000

3.783913917

4.4750000000%

0.00

1,202.87

0.054747262

4.4750000000%

0.000000000

361849P97

21,971,327.00

0.00

21,971,327.00

83,137.61

21,971,327.00

0.000000000

0.00

0.000000000

N/A

0.000000000

111322640

R-III

0.00

0.000000000

0.00

0.000000000

N/A

0.000000000

111322624

R-I

0.00

0.000000000

0.00

0.000000000

N/A

0.000000000

111322632

R-II

0.00

Total P&I Payment

0.00

1,202.87

1,597,857,327.00

1,594,788,538.11

7,928,510.59

Total

1,594,107,371.15

681,166.96

0.00

7,247,343.63

Page 3 of 33

Class

CUSIP

Original

Opening

Principal

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

WAC:
WAMM:

Payment Date:
Prior Payment:
Next Payment:
Record Date:

5.503548%

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

GMAC Commercial Mortgage Securities, Inc.

Mortgage Pass-Through Certificates

Series 2005-C1

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

Grantor Trust Q

Statement Date:

ABN AMRO Acct: 722718.1

0.000000000

0.00

0.000000000

N/A

0.000000000

111322608

0.00

Total P&I Payment

0.00

Total

0.00

Page 4 of 33

Class

CUSIP

Original

Opening

Principal

Negative

Closing

Interest

Pass-Through

Per $ 1000

Next Rate(3)

WAC:
WAMM:

Payment Date:
Prior Payment:
Next Payment:
Record Date:

5.503548%

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

GMAC Commercial Mortgage Securities, Inc.

Mortgage Pass-Through Certificates

Series 2005-C1

Face Value (1)

Balance

Payment

Adj. or Loss

Amortization

Balance

Payment (2)

Adjustment

Rate

Grantor Trust W

Statement Date:

ABN AMRO Acct: 722718.1

0.000000000

0.00

0.000000000

N/A

0.000000000

111322616

0.00

Total P&I Payment

0.00

Total

0.00

Page 5 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Statement Date:

Cash Reconciliation Summary

Current Scheduled Interest

Interest Summary

Less Deferred Interest

Plus Gross Advance Interest

Less PPIS Reducing Scheduled Int

7,314,162.11

0.00
0.00

Less ASER Interest Adv Reduction

0.00

Less Other Adjustment

0.00

Total

7,314,162.11

Unscheduled Interest:
Prepayment Penalties

0.00

Yield Maintenance Penalties

0.00

Other Interest Proceeds

3,318.88

Total

3,318.88

Less Fees & Expenses Paid By/To Servicer

Less Fee Paid To Servicer
Less Fee Strips Paid by Servicer

Special Servicing Fees

Interest Due Serv on Advances
Recoup of Prior Advances
Misc. Fees & Expenses

Total Unscheduled Fees &
Expenses

Total Interest Due Trust

Less Fees & Expenses Paid By/To Trust
Trustee Fee
Fee Strips

Interest Reserve Withholding

Plus Interest Reserve Deposit
Total

Total Interest Due Certs

Principal Summary

Scheduled Principal:
Current Scheduled Principal
Advanced Scheduled Principal
Scheduled Principal
Unscheduled Principal:
Curtailments
Prepayments in Full
Liquidation Proceeds
Repurchase Proceeds
Other Principal Proceeds
Total Unscheduled Principal
Remittance Principal

Remittance P&I Due Trust

Remittance P&I Due Certs

Pool Balance Summary

Beginning Pool
Scheduled Principal
Unscheduled Principal
Deferred Interest
Liquidations
Repurchases

Ending Pool

Balance

Count

Principal

Interest

Prior Outstanding
Plus Current Period
Less Recovered

Ending Outstanding

Servicing Fee Summary

Current Servicing Fees
Plus Fees Advanced for PPIS
Less Reduction for PPIS
Plus Delinquent Servicing Fees

Total Servicing Fees

PPIS Summary

Gross PPIS
Reduced by PPIE
Reduced by Shortfalls in Fees
Reduced by Other Amounts

PPIS Reducing Scheduled
Interest

PPIS Reducing Servicing Fee
PPIS Due Certificate

0.00

0.00
0.00

)

(2,116.01

)

(2,116.01

7,249,071.33

)

(1,727.69

0.00
0.00
0.00

)

(1,727.69

681,166.96

0.00

681,166.96

0.00
0.00
0.00
0.00
0.00
0.00

681,166.96

7,930,238.29

7,928,510.60

1,594,788,538.99

681,166.96

0.00

0.00
0.00

0.00

1,594,107,372.03

31,716.27

241,795.65

0.00

66,293.65

0.00
0.00
0.00

66,293.65

0.00
0.00
0.00
0.00
0.00
0.00

0.00

)

(66,293.65

7,247,343.64

Interest Not Advanced (

Current Period

)

0.00

Workout Fees
Liquidation Fees

0.00
0.00

Less Non Recovered

)

(241,795.65

)

(31,716.27

0.00

Advance Summary (Advance Made by Servicer)

0.00

Misc. Fees

Page 6 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Statement Date:

Cash Reconciliation Summary Group I Loans

Current Scheduled Interest

Interest Summary

Less Deferred Interest

Plus Gross Advance Interest

Less PPIS Reducing Scheduled Int

5,714,588.78

0.00
0.00

Less ASER Interest Adv Reduction

0.00

Less Other Adjustment

0.00

Total

5,714,588.78

Unscheduled Interest:
Prepayment Penalties

0.00

Yield Maintenance Penalties

0.00

Other Interest Proceeds

0.00

Total

0.00

Less Fees & Expenses Paid By/To Servicer

Less Fee Paid To Servicer
Less Fee Strips Paid by Servicer

Special Servicing Fees

Interest Due Serv on Advances
Recoup of Prior Advances
Misc. Fees & Expenses

Total Unscheduled Fees &
Expenses

Total Interest Due Trust

Less Fees & Expenses Paid By/To Trust
Trustee Fee
Fee Strips

Interest Reserve Withholding

Plus Interest Reserve Deposit
Total

Total Interest Due Certs

Principal Summary

Remittance P&I Due Trust

Remittance P&I Due Certs

Pool Balance Summary

Beginning Pool
Scheduled Principal
Unscheduled Principal
Deferred Interest
Liquidations
Repurchases

Ending Pool

Balance

Count

Principal

Interest

Prior Outstanding
Plus Current Period
Less Recovered

Ending Outstanding

Servicing Fee Summary

Current Servicing Fees
Plus Fees Advanced for PPIS
Less Reduction for PPIS
Plus Delinquent Servicing Fees

Total Servicing Fees

PPIS Summary

Gross PPIS
Reduced by PPIE
Reduced by Shortfalls in Fees
Reduced by Other Amounts

PPIS Reducing Scheduled
Interest

PPIS Reducing Servicing Fee
PPIS Due Certificate

0.00

0.00
0.00

)

(855.21

)

(855.21

5,662,156.00

)

(1,354.76

0.00
0.00
0.00

)

(1,354.76

619,226.05

0.00

619,226.05

0.00
0.00
0.00
0.00
0.00
0.00

619,226.05

6,281,382.05

6,280,027.28

1,250,551,580.12

619,226.05

0.00

0.00
0.00

0.00

1,249,932,354.07

0.00

51,577.57

0.00
0.00
0.00

51,577.57

0.00
0.00
0.00
0.00
0.00
0.00

0.00

)

(51,577.57

5,660,801.23

Interest Not Advanced (

Current Period

)

0.00

Workout Fees
Liquidation Fees

0.00
0.00

Less Non Recovered

0.00

0.00
0.00

0.00

Advance Summary (Advance Made by Servicer)

0.00

Misc. Fees

Page 7 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Statement Date:

Cash Reconciliation Summary Group II Loans

Current Scheduled Interest

Interest Summary

Less Deferred Interest

Plus Gross Advance Interest

Less PPIS Reducing Scheduled Int

1,599,573.33

0.00
0.00

Less ASER Interest Adv Reduction

0.00

Less Other Adjustment

0.00

Total

1,599,573.33

Unscheduled Interest:
Prepayment Penalties

0.00

Yield Maintenance Penalties

0.00

Other Interest Proceeds

3,318.88

Total

3,318.88

Less Fees & Expenses Paid By/To Servicer

Less Fee Paid To Servicer
Less Fee Strips Paid by Servicer

Special Servicing Fees

Interest Due Serv on Advances
Recoup of Prior Advances
Misc. Fees & Expenses

Total Unscheduled Fees &
Expenses

Total Interest Due Trust

Less Fees & Expenses Paid By/To Trust
Trustee Fee
Fee Strips

Interest Reserve Withholding

Plus Interest Reserve Deposit
Total

Total Interest Due Certs

Principal Summary

Remittance P&I Due Trust

Remittance P&I Due Certs

Pool Balance Summary

Beginning Pool
Scheduled Principal
Unscheduled Principal
Deferred Interest
Liquidations
Repurchases

Ending Pool

Balance

Count

Principal

Interest

Prior Outstanding
Plus Current Period
Less Recovered

Ending Outstanding

Servicing Fee Summary

Current Servicing Fees
Plus Fees Advanced for PPIS
Less Reduction for PPIS
Plus Delinquent Servicing Fees

Total Servicing Fees

PPIS Summary

Gross PPIS
Reduced by PPIE
Reduced by Shortfalls in Fees
Reduced by Other Amounts

PPIS Reducing Scheduled
Interest

PPIS Reducing Servicing Fee
PPIS Due Certificate

0.00

0.00
0.00

)

(1,260.80

)

(1,260.80

1,586,915.33

)

(372.92

0.00
0.00
0.00

)

(372.92

61,940.91

0.00

61,940.91

0.00
0.00
0.00
0.00
0.00
0.00

61,940.91

1,648,856.24

1,648,483.32

344,236,958.87

61,940.91

0.00

0.00
0.00

0.00

344,175,017.96

31,716.27

241,795.65

0.00

14,716.08

0.00
0.00
0.00

14,716.08

0.00
0.00
0.00
0.00
0.00
0.00

0.00

)

(14,716.08

1,586,542.41

Interest Not Advanced (

Current Period

)

0.00

Workout Fees
Liquidation Fees

0.00
0.00

Less Non Recovered

)

(241,795.65

)

(31,716.27

0.00

Advance Summary (Advance Made by Servicer)

0.00

Misc. Fees

Page 8 of 33

GMAC Commercial Mortgage Securities, Inc.

Class

Accrued

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Bond Interest Reconciliation

Deductions

Allocable

Deferred &

Prior

Prepay-

Other

Additions

Interest

Credit Support

Original

Current(4)

Accrual

Int. Short-

falls Due

ment

Interest

Int erest (2)

Payment

Amount

PPIS

Int erest

Certificate

Accretion

Interest

Loss/Exp

Interest

Penalties

Proceeds (1)

Interest

Shortfalls

Certificate

Rate

Pass

Thru

Method Days

Outstanding

Remaining

Statement Date:

Distributable

Current Period

(Shortfall)/

Recovery

Int Accrual

on Prior

Shortfall (3)

3.00
1.00

0.00

A-1

204,795.20

0.00

30.00%

30.07%

30/360

4.208000000%

0.00

A-1A

1,323,876.35

0.00

30.00%

30.07%

30/360

4.615000000%

0.00

A-2

1,117,750.00

0.00

30.00%

30.07%

30/360

4.471000000%

0.00

A-3

708,306.17

0.00

30.00%

30.07%

30/360

4.538000000%

0.00

A-4

262,128.25

0.00

30.00%

30.07%

30/360

4.619000000%

0.00

A-5

616,062.43

0.00

30.00%

30.07%

30/360

4.697000000%

0.00

X-1

128,220.98

0.00

30/360

0.096479988%

0.00

X-2

962,197.71

0.00

30/360

0.774523552%

0.00

A-M

633,014.91

0.00

20.00%

20.05%

30/360

4.754000000%

0.00

A-J

511,955.14

0.00

12.00%

12.03%

30/360

4.806000000%

0.00

139,664.12

0.00

9.88%

9.90%

30/360

4.936000000%

0.00

49,813.49

0.00

9.13%

9.15%

30/360

4.988000000%

0.00

101,005.15

0.00

7.63%

7.64%

30/360

5.057000000%

0.00

68,643.12

0.00

6.63%

6.64%

30/360

5.155000000%

0.00

64,444.60

0.00

5.63%

5.64%

30/360

4.840000000%

0.00

65,473.95

0.00

4.63%

4.64%

30/360

4.917000000%

0.00

87,681.47

0.00

3.38%

30/360

5.268000000%

0.00

22,345.17

0.00

3.00%

3.01%

30/360

4.475000000%

0.00

22,345.17

0.00

2.63%

30/360

4.475000000%

0.00

29,792.31

0.00

2.13%

30/360

4.475000000%

0.00

14,898.02

0.00

1.88%

30/360

4.475000000%

0.00

14,898.02

0.00

1.63%

30/360

4.475000000%

0.00

14,894.29

0.00

1.38%

30/360

4.475000000%

0.00

81,934.74

88,114.49

83,137.61

4,976.88

0.00%

30/360

4.475000000%

1,202.87

6,179.75

0.00

0.000000000%

0.00

0.000000000%

0.00

7,246,140.76

7,252,320.51

7,247,343.63

4,976.88

1,202.87

6,179.75

0.00

(2) Accrued - Deductions + Additions Interest

(3) Includes interest accrued on outstanding Interest Shortfalls and/or Loss Allocations. Where applicable.

Page 9 of 33

(1) Other Interest Proceeds are additional interest amounts specifically allocated to the bond(s) and used in determining the bonds Distributable Interest.

(4) Determined as follows: (A) the ending balance of all the classes less (B) the sum of (i) the ending balance of the class and (ii) the ending balance of all classes which are not subordinate to the class divided by (A).

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Interest Adjustments Summary

Statement
Date:

0.00

Special Servicing Fees

Workout Fees

Liquidation Fees

Legal Fees

0.00

Misc. Fees & Expenses Paid by/to Servicer

Interest Paid to Servicer on Outstanding Advances

2,116.01

0.00

ASER Interest Advance Reduction

Interest Not Advanced (Current Period)

Recoup of Prior Advances by Servicer

0.00

Servicing Fees Paid Servicer on Loans Not Advanced

Misc. Fees & Expenses Paid by Trust

0.00

Shortfall Due to Rate Modification

Total Shortfall Allocated to the Bonds

Total Interest Adjustment to the Bonds

2,116.01

Shortfall Allocated to the Bonds:

Excess Allocated to the Bonds:

Other Interest Proceeds Due the Bonds

Yield Maintenance Penalties Due the Bonds

Prepayment Penalties Due the Bonds

Recovered ASER Interest Due the Bonds

Recovered Interest Due the Bonds

Less Total Shortfall Allocated to the Bonds

Total Excess Allocated to the Bonds

3,318.88

3,318.88

Total Excess Allocated to the Bonds

1,202.87

)

(2,116.01

Aggregate Interest Adjustment Allocated to the Bonds

0.00

Prepayment Interest Excess Due the Bonds

0.00

ARD Excess Interest

0.00

3,318.88

Net Prepayment Int. Shortfalls Allocated to the Bonds

Other Interest Loss

Interest Income

0.00

Page 10 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Rating Information

Class

CUSIP

Fitch

Moody's

S&P

Fitch

Moody's

S&P

Original Ratings

Rating Change/Change Date(1)

Statement Date:

A-1

361849M41

AAA

A-1A

361849M58

AAA

A-2

361849M66

AAA

A-3

361849M74

AAA

A-4

361849M82

AAA

A-5

361849Q21

AAA

X-1

361849N65

AAA

X-2

361849M90

AAA

A-M

361849Q39

AAA

A-J

361849N24

AAA

361849N32

361849N40

AA-

361849N57

361849N73

A-

361849N81

BBB+

361849N99

BBB

361849P22

BBB-

361849P30

BB+

361849P48

361849P55

BB-

361849P63

B+

361849P71

Page 11 of 33

NR - Designates that the class was not rated by the rating agency.

(1)

Changed ratings provided on this report are based on information provided by the applicable rating agency via electronic transmission. It shall be understood that this transmission will generally have been provided to

LaSalle within 30 days of the payment date listed on this statement. Because ratings may have changed during the 30 day window, or may not be being provided by the rating agency in an electronic format and therefore not
being updated on this report, LaSalle recommends that investors obtain current rating information directly from the rating agency.

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Rating Information

Class

CUSIP

Fitch

Moody's

S&P

Fitch

Moody's

S&P

Original Ratings

Rating Change/Change Date(1)

Statement Date:

361849P89

B-

361849P97

111322608

111322616

Page 12 of 33

NR - Designates that the class was not rated by the rating agency.

(1)

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary

Distribution

Date

Delinq 1 Month

Delinq 2 Months

Delinq 3+ Months

Foreclosure

REO

Modifications

Specially Serviced

Bankruptcy

# Balance

Delinquency Aging Categories

Special Event Categories (1)

Statement Date:

ABN AMRO Acct: 722718.1

0.00%

12/12/2005

0.00

1.10%

1.34%

0.00%

11/10/2005

21,307,574.72

0.00

1.10%

0.23%

2.20%

2.54%

0.00%

10/11/2005

3,700,000.00

40,450,647.10

0.00

2.20%

2.54%

0.00%

9/12/2005

40,484,566.67

0.00

0.00%

8/10/2005

0.00

0.00%

7/11/2005

0.00

(1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category

Page 13 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary

Distribution

Date

Delinq 1 Month

Delinq 2 Months

Delinq 3+ Months

Foreclosure

REO

Modifications

Specially Serviced

Bankruptcy

# Balance

Delinquency Aging Categories

Special Event Categories (1)

Statement Date:

Group I Loans

ABN AMRO Acct: 722718.1

0.00%

12/12/2005

0.00

0.00%

11/10/2005

0.00

0.00%

10/11/2005

0.00

0.00%

9/12/2005

0.00

0.00%

8/10/2005

0.00

0.00%

7/11/2005

0.00

(1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category

Page 14 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

Asset-Backed Facts ~ 15 Month Historical Loan Status Summary

Distribution

Date

Delinq 1 Month

Delinq 2 Months

Delinq 3+ Months

Foreclosure

REO

Modifications

Specially Serviced

Bankruptcy

# Balance

Delinquency Aging Categories

Special Event Categories (1)

Statement Date:

Group II Loans

ABN AMRO Acct: 722718.1

0.00%

12/12/2005

0.00

4.76%

6.19%

0.00%

11/10/2005

21,307,574.72

0.00

4.76%

1.07%

9.52%

11.75%

0.00%

10/11/2005

3,700,000.00

40,450,647.10

0.00

9.52%

11.76%

0.00%

9/12/2005

40,484,566.67

0.00

0.00%

8/10/2005

0.00

0.00%

7/11/2005

0.00

(1) Note: Modification, Specially Serviced & Bankruptcy Totals are Included in the Appropriate Delinquency Aging Category

Page 15 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary

Distribution

Date

Ending Pool (1)

Payoffs(2)

Penalties

Appraisal Reduct. (2)

Liquidations (2)

Realized Losses (2)

Remaining Term

Curr Weighted Avg.

# Balance

# Amount

# Balance

# Amount

Life

Coupon Remit

Statement Date:

Amort

ABN AMRO Acct: 722718.1

Series 2005-C1

12-Dec-05

100.00%

1,594,107,372

99.77%

0.00%

239

5.50%

5.45%

10-Nov-05

100.00%

1,594,788,539

99.81%

0.00%

239

5.70%

5.65%

11-Oct-05

100.00%

1,595,381,923

99.85%

0.00%

240

5.50%

5.45%

12-Sep-05

100.00%

1,596,047,048

99.89%

0.00%

241

5.70%

5.65%

10-Aug-05

100.00%

1,596,625,274

99.92%

0.00%

242

5.70%

5.65%

11-Jul-05

100.00%

1,597,200,709

99.96%

0.00%

242

5.50%

5.45%

(1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period.

Page 16 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary

Distribution

Date

Ending Pool (1)

Payoffs(2)

Penalties

Appraisal Reduct. (2)

Liquidations (2)

Realized Losses (2)

Remaining Term

Curr Weighted Avg.

# Balance

# Amount

# Balance

# Amount

Life

Coupon Remit

Statement Date:

Group I Loans

Amort

ABN AMRO Acct: 722718.1

Series 2005-C1

12-Dec-05

76.92%

1,249,932,354

78.23%

0.00%

243

5.48%

5.43%

10-Nov-05

76.92%

1,250,551,580

78.26%

0.00%

244

5.69%

5.64%

11-Oct-05

76.92%

1,251,094,931

78.30%

0.00%

245

5.48%

5.43%

12-Sep-05

76.92%

1,251,698,708

78.34%

0.00%

246

5.69%

5.64%

10-Aug-05

76.92%

1,252,227,510

78.37%

0.00%

246

5.69%

5.64%

11-Jul-05

76.92%

1,252,753,791

78.40%

0.00%

247

5.48%

5.43%

(1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period.

Page 17 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Asset-Backed Facts ~ 15 Month Historical Payoff/Loss Summary

Distribution

Date

Ending Pool (1)

Payoffs(2)

Penalties

Appraisal Reduct. (2)

Liquidations (2)

Realized Losses (2)

Remaining Term

Curr Weighted Avg.

# Balance

# Amount

# Balance

# Amount

Life

Coupon Remit

Statement Date:

Group II Loans

Amort

ABN AMRO Acct: 722718.1

Series 2005-C1

12-Dec-05

23.08%

344,175,018

21.54%

0.00%

222

5.58%

5.52%

10-Nov-05

23.08%

344,236,959

21.54%

0.00%

223

5.76%

5.71%

11-Oct-05

23.08%

344,286,992

21.55%

0.00%

223

5.58%

5.52%

12-Sep-05

23.08%

344,348,340

21.55%

0.00%

224

5.76%

5.71%

10-Aug-05

23.08%

344,397,764

21.55%

0.00%

225

5.76%

5.71%

11-Jul-05

23.08%

344,446,919

21.56%

0.00%

225

5.58%

5.52%

(1) Percentage based on pool as of cutoff. (2) Percentage based on pool as of beginning of period.

Page 18 of 33

GMAC Commercial Mortgage Securities, Inc.

Mortgage Loan Characteristics

ABN AMRO Acct: 722718.1

Series 2005-C1

Mortgage Pass-Through Certificates

30-Nov-05

10-Jan-06

10-Nov-05

12-Dec-05

Record Date:

Next Payment:

Prior Payment:

Payment Date:

Statement Date:

Distribution of Mortgage Interest Rates

Distribution of Principal Balances

Distribution of Remaining Term (Balloon)

Distribution of Remaining Term (Fully Amortizing)

Page 19 of 33

Current Scheduled

Balance

# of

Loans

Scheduled

Balance

% of

Balance

Weighted Average

Term Coupon PFY DSCR

793,362

0.05

112

5.88

0.00

0 to

2,000,000

9,715,508

0.61

145

5.51

0.00

2,000,000 to

3,000,000

42,907,611

2.69

111

5.59

0.00

3,000,000 to

4,000,000

48,253,005

3.03

121

5.49

0.00

4,000,000 to

6,000,000

91,130,088

5.72

104

5.40

0.00

6,000,000 to

8,000,000

53,679,125

3.37

103

5.52

0.00

8,000,000 to 10,000,000

222,155,203

13.94

110

5.45

0.00

10,000,000 to 15,000,000

415,684,939

26.08

102

5.54

0.00

15,000,000 to 30,000,000

44,106,711

2.77

112

5.19

0.00

30,000,000 to 50,000,000

665,681,820

41.76

5.53

0.00

50,000,000 &

Above

180,000,000

793,362

1,594,107,372

100.00

Average Schedule Balance
Maximum Schedule Balance
Minimum Schedule Balance

17,517,663

Current Mortgage

Interest Rate

# of

Loans

Scheduled

Balance

% of

Balance

Weighted Average

Term Coupon PFY DSCR

44,508,961

2.79

112

4.85

0.00

0.100%

4.999%

310,258,818

19.46

5.13

0.00

5.000%

5.249%

698,277,020

43.80

5.40

0.00

5.250%

5.499%

270,077,277

16.94

5.63

0.00

5.500%

5.749%

133,966,869

8.40

105

5.86

0.00

5.750%

5.999%

96,628,301

6.06

6.42

0.00

6.000%

6.499%

40,390,124

2.53

113

6.71

0.00

6.500%

Above

1,594,107,372

Minimum Mortgage Interest Rate
Maximum Mortgage Interest Rate

100.00

4.766%
6.720%

Fully Amortizing

Mortgage Loans

# of

Loans

Scheduled

Balance

% of

Balance

Weighted Average

Term Coupon PFY DSCR

0.00

150

0.00

151

225

10,940,273

0.69

231

5.86

0.00

226

300

0.00

301

Above

234

230

10,940,273

Minimum Remaining Term
Maximum Remaining Term

0.69

Balloon

Mortgage Loans

# of

Loans

Scheduled

Balance

% of

Balance

Weighted Average

Term Coupon PFY DSCR

0.00

659,225,451

41.35

5.56

0.00

7,500,000

0.47

5.30

0.00

4,500,000

0.28

5.30

0.00

100

875,350,060

54.91

112

5.45

0.00

101

120

11,798,294

0.74

136

5.35

0.00

121

140

24,793,294

1.56

168

5.84

0.00

141

& Above

168

1,583,167,099

Minimum Remaining Term
Maximum Remaining Term

99.31

GMAC Commercial Mortgage Securities, Inc.

Mortgage Loan Characteristics

ABN AMRO Acct: 722718.1

Series 2005-C1

Mortgage Pass-Through Certificates

30-Nov-05

10-Jan-06

10-Nov-05

12-Dec-05

Record Date:

Next Payment:

Prior Payment:

Payment Date:

Statement Date:

Geographic Distribution

Distribution of DSCR (PFY)

Distribution of DSCR (Cutoff)

Page 20 of 33

Debt Service

Coverage Ratio

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

0.00

0.010 1.090

0.00

1.100 1.190

0.00

1.200 1.290

0.00

1.300 1.390

0.00

1.400 1.490

0.00

1.500 1.590

0.00

1.600 1.690

0.00

1.700 1.790

0.00

1.800 1.890

0.00

1.900 1.990

0.00

2.000 & Above

1,594,107,372

100.00

5.50

0.00

Unknown

0.000
0.000

1,594,107,372

100.00

Minimum DSCR

Maximum DSCR

Debt Service

Coverage Ratio

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

0.00

0.010 1.000

2,764,048

0.17

234

5.88

0.00

1.001 1.100

24,643,698

1.55

131

5.54

0.00

1.101 1.200

634,248,787

39.79

5.51

0.00

1.201 1.300

327,297,572

20.53

5.76

0.00

1.301 1.400

84,698,411

5.31

5.62

0.00

1.401 1.500

228,315,723

14.32

5.47

0.00

1.501 1.600

43,233,724

2.71

118

5.55

0.00

1.601 1.700

5,061,768

0.32

113

5.28

0.00

1.701 1.800

7,491,317

0.47

113

5.40

0.00

1.801 1.900

3,800,000

0.24

111

5.24

0.00

1.901 2.000

0.00

2.001 2.100

27,000,000

1.69

109

5.30

0.00

2.101 2.200

25,552,323

1.60

112

4.80

0.00

2.201 2.300

180,000,000

11.29

5.13

0.00

2.301 & Above

2.380

1.050

1,594,107,372 100.00

Minimum DSCR

Maximum DSCR

Geographic

Location

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

New York

289,048,836

18.13

5.32

0.00

California

194,073,856

12.17

5.55

0.00

New Jersey

168,549,293

10.57

106

5.47

0.00

Texas

134,625,544

8.45

108

5.74

0.00

Undefined

105,997,049

6.65

6.36

0.00

Nevada

77,518,905

4.86

5.48

0.00

Michigan

76,944,767

4.83

5.50

0.00

Florida

75,644,962

4.75

101

5.18

0.00

Connecticut

63,300,000

3.97

111

5.49

0.00

Arkansas

56,938,294

3.57

119

5.44

0.00

Missouri

44,106,711

2.77

112

5.19

0.00

North Carolina

38,250,000

2.40

111

5.14

0.00

Colorado

36,340,257

2.28

104

5.39

0.00

Georgia

33,093,153

2.08

112

5.42

0.00

Maryland

31,178,380

1.96

5.59

0.00

District of Columbia

27,000,000

1.69

109

5.30

0.00

Pennsylvania

24,784,075

1.55

112

5.30

0.00

Virginia

23,355,592

1.47

110

5.35

0.00

Arizona

20,525,444

1.29

5.92

0.00

Washington

15,923,744

1.00

141

5.39

0.00

Illinois

12,400,000

0.78

114

5.27

0.00

New Hampshire

10,915,359

0.68

112

5.43

0.00

Utah

7,060,715

0.44

5.14

0.00

Oregon

6,873,341

0.43

5.31

0.00

Kentucky

4,452,481

0.28

230

6.08

0.00

Delaware

4,365,873

0.27

113

5.12

0.00

Alabama

3,774,799

0.24

113

5.84

0.00

Mississippi

3,700,000

0.23

5.58

0.00

West Virginia

3,365,940

0.21

113

5.74

0.00

100.00

1,594,107,372

GMAC Commercial Mortgage Securities, Inc.

Mortgage Loan Characteristics

ABN AMRO Acct: 722718.1

Series 2005-C1

Mortgage Pass-Through Certificates

30-Nov-05

10-Jan-06

10-Nov-05

12-Dec-05

Record Date:

Next Payment:

Prior Payment:

Payment Date:

Statement Date:

Distribution of Loan Seasoning

Distribution of Property Types

Distribution of Year Loans Maturing

Distribution of Amortization Type

Page 21 of 33

Property Types

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

Office

659,348,893

41.36

5.40

0.00

Multifamily

344,175,018

21.59

5.58

0.00

Retail

244,997,987

15.37

113

5.45

0.00

Lodging

147,875,212

9.28

5.93

0.00

Industrial

93,684,399

5.88

118

5.38

0.00

Other

47,798,485

3.00

5.66

0.00

Self Storage

23,966,663

1.50

111

5.75

0.00

Mixed Use

17,860,715

1.12

5.27

0.00

Mobile Home Park

14,400,000

0.90

114

5.17

0.00

1,594,107,372

100.00

Amortization Type

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

Amortizing Balloon

505,137,090

31.69

5.74

0.00

Amortizing/IO

24,793,294

1.56

168

5.84

0.00

Full Amortizing

10,940,273

0.69

231

5.86

0.00

IO Maturity Balloon

465,550,000

29.20

5.38

0.00

IO/Amortizing

587,686,715

36.87

104

5.38

0.00

1,594,107,372

100.00

Number of Months

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

0.00

100,000,000

6.27

0.00

5.46

155,388,755

9.75

116

0.00

5.46

349,310,609

21.91

0.00

5.88

363,647,809

22.81

102

0.00

5.41

230,995,510

14.49

0.00

5.45

260,497,868

16.34

0.00

5.21

134,266,820

8.42

112

0.00

5.54

1,594,107,372

100.00

Year

# of

Loans

Scheduled

Balance

% of

Balance

WAMM WAC PFY DSCR

0.00

2005

0.00

2006

0.00

2007

0.00

2008

7,060,715

0.44

5.14

0.00

2009

652,164,736

40.91

5.56

0.00

2010

0.00

2011

7,500,000

0.47

5.30

0.00

2012

4,500,000

0.28

5.30

0.00

2013

21,108,124

1.32

108

5.73

0.00

2014

854,241,936

53.59

112

5.45

0.00

2015

47,531,861

2.98

175

5.72

0.00

2016 & Greater

100.00

1,594,107,372

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Delinquent Loan Detail

Disclosure

Control #

Paid
Thru
Date

Current P&I

Advance

Outst anding

P& I

Advances**

Out. Property

Protection
Advances

Loan Status

Code (1)

Special

Servicer

Transfer Date

Foreclosure

Date

Bankruptcy

Date

REO

Date

Statement Date:

Total

Page 22 of 33

A. In Grace Period

1. Delinq. 1 month

2. Delinq. 2 months

3. Delinquent 3 + months

4. Performing Matured Balloon

** Outstanding P&I Advances include the current period P&I Advances and may include Servicer and Trust Advances.

7. Foreclosure

9. REO

B. Late Payment but < 1 month delinq.

5. Non Performing Matured Balloon

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Historical Collateral Level Prepayment Report

Disclosure

Control #

Payoff

Period

Initial

Balance

Type

Payoff

Amount

Penalty

Amount

Prepayment

Date

Maturity

Date

Property

Type

Geographic

Location

Statement Date:

Cumulative

Current

Page 23 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Loan Level Detail

Disclosure

Control #

Group

Property

Type

Maturity

Date

PFY

DSCR

Operating
Statement

Date

Geo.

Location

Ending

Principal

Balance

Note
Rate

Scheduled

P&I

Prepayment

Amount

Prepayment

Date

Loan

Status

Code (1)

Statement Date:

5.13%

1-Feb-10

GMAC5C1A

Office

0.00

180,000,000

769,189

5.63%

1-Mar-10

GMAC5C1A

Office

0.00

100,000,000

469,216

5.46%

8-Jun-10

GMAC5C1B

Multifamily

0.00

100,000,000

455,000

6.44%

1-Nov-10

GMAC5C1A

Lodging

0.00

92,175,820

624,460

5.49%

1-Apr-15

GMAC5C1A

Office

0.00

79,686,000

364,563

5.44%

1-May-10

GMAC5C1A

Office

0.00

57,750,000

261,800

5.38%

1-Mar-15

GMAC5C1A

Office

0.00

56,070,000

251,381

5.19%

1-Apr-15

GMAC5C1A

Office

0.00

44,106,711

244,080

5.26%

1-Apr-15

GMAC5C1A

Industrial

0.00

21,500,000

94,242

5.26%

1-Apr-15

GMAC5C1A

Industrial

0.00

20,500,000

89,858

5.30%

1-Jan-15

GMAC5C1A

Lodging

0.00

27,000,000

119,250

5.84%

1-Apr-10

GMAC5C1A

Other

0.00

26,198,485

168,157

5.30%

1-Apr-15

GMAC5C1A

Retail

0.00

24,784,075

138,826

4.77%

1-Apr-15

GMAC5C1A

Lodging

0.00

24,758,961

130,653

5.84%

1-Dec-19

GMAC5C1A

Office

0.00

24,793,294

138,673

5.62%

1-Apr-10

GMAC5C1B

Multifamily

0.00

24,500,000

114,742

5.71%

1-May-10

GMAC5C1B

Multifamily

0.00

24,000,000

114,200

5.47%

1-Jun-15

GMAC5C1B

Multifamily

0.00

23,000,000

104,842

5.45%

1-Jan-15

GMAC5C1A

Other

0.00

21,600,000

98,100

6.72%

1-May-15

GMAC5C1B

Multifamily

0.00

21,289,511

137,386

5.11%

1-Apr-15

GMAC5C1B

Multifamily

0.00

21,250,000

90,490

5.35%

8-Apr-15

GMAC5C1A

Retail

0.00

20,760,000

92,555

4.96%

1-Mar-15

GMAC5C1B

Multifamily

0.00

19,750,000

81,633

Page 24 of 33

* NOI and DSCR, if available and reportable under the terms of the trust agreement, are based on information obtained from the related borrower, and no other party to the agreement shall be held liable for the accuracy or methodology used to

determine such figures.

(1) Legend:

A. In Grace Period

B. Late Payment but < 1 month delinq

1. Delinquent 1 month
2. Delinquent 2 months

3. Delinquent 3+ months

4. Performing Matured Balloon

7. Foreclosure

9. REO

5. Non Performing Matured Ballon

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Loan Level Detail

Disclosure

Control #

Group

Property

Type

Maturity

Date

PFY

DSCR

Operating
Statement

Date

Geo.

Location

Ending

Principal

Balance

Note
Rate

Scheduled

P&I

Prepayment

Amount

Prepayment

Date

Loan

Status

Code (1)

Statement Date:

6.69%

1-May-15

GMAC5C1B

Multifamily

0.00

19,100,614

122,783

5.35%

1-Mar-15

GMAC5C1A

Retail

0.00

17,500,000

78,021

5.95%

1-Apr-10

GMAC5C1A

Office

0.00

17,400,000

86,275

5.43%

1-May-15

GMAC5C1A

Retail

0.00

16,000,000

72,400

5.32%

1-Jun-15

GMAC5C1A

Industrial

0.00

14,880,000

65,906

5.01%

1-Feb-10

GMAC5C1A

Retail

0.00

14,500,000

60,538

5.17%

1-Jun-15

GMAC5C1A

Mobile Home Park

0.00

14,400,000

62,040

5.62%

1-Jun-15

GMAC5C1A

Retail

0.00

14,000,000

65,567

5.45%

1-May-15

GMAC5C1A

Office

0.00

13,898,826

79,052

5.35%

1-Feb-15

GMAC5C1B

Multifamily

0.00

13,600,000

60,633

5.47%

1-May-15

GMAC5C1B

Multifamily

0.00

13,500,000

61,549

5.27%

1-Jun-15

GMAC5C1A

Office

0.00

12,400,000

54,457

5.33%

1-Jun-15

GMAC5C1B

Multifamily

0.00

12,200,000

54,188

5.84%

1-Apr-15

GMAC5C1A

Office

0.00

12,106,130

71,895

5.35%

1-Apr-17

GMAC5C1A

Retail

0.00

11,798,294

66,451

5.80%

1-Jan-15

GMAC5C1B

Multifamily

0.00

11,155,852

66,188

5.43%

1-Apr-15

GMAC5C1A

Retail

0.00

10,915,359

67,396

5.54%

1-May-15

GMAC5C1A

Office

0.00

10,922,048

62,733

5.35%

1-Mar-15

GMAC5C1A

Mixed Use

0.00

10,800,000

48,150

5.84%

1-Jun-15

GMAC5C1A

Retail

0.00

10,700,000

52,073

5.96%

1-Dec-14

GMAC5C1A

Self Storage

0.00

10,291,324

67,203

5.35%

1-Feb-15

GMAC5C1A

Industrial

0.00

10,087,370

56,958

5.49%

1-Feb-15

GMAC5C1A

Retail

0.00

9,843,153

56,433

Page 25 of 33

determine such figures.

(1) Legend:

A. In Grace Period

B. Late Payment but < 1 month delinq

1. Delinquent 1 month
2. Delinquent 2 months

3. Delinquent 3+ months

4. Performing Matured Balloon

7. Foreclosure

9. REO

5. Non Performing Matured Ballon

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Loan Level Detail

Disclosure

Control #

Group

Property

Type

Maturity

Date

PFY

DSCR

Operating
Statement

Date

Geo.

Location

Ending

Principal

Balance

Note
Rate

Scheduled

P&I

Prepayment

Amount

Prepayment

Date

Loan

Status

Code (1)

Statement Date:

5.55%

1-May-15

GMAC5C1A

Retail

0.00

9,581,764

55,095

5.70%

1-Feb-15

GMAC5C1A

Retail

0.00

8,907,352

52,236

5.66%

1-Jun-15

GMAC5C1A

Retail

0.00

8,846,857

51,430

5.62%

1-Jun-15

GMAC5C1A

Retail

0.00

8,500,000

39,808

5.06%

1-Jan-10

GMAC5C1B

Multifamily

0.00

8,000,000

33,733

5.37%

1-Jun-15

GMAC5C1A

Retail

0.00

7,651,026

43,070

5.32%

1-Jun-15

GMAC5C1A

Industrial

0.00

7,760,000

34,370

5.30%

1-Mar-12

GMAC5C1A

Office

0.00

7,500,000

33,125

5.50%

1-Mar-15

GMAC5C1A

Office

0.00

7,291,869

41,789

5.53%

1-Dec-14

GMAC5C1B

Multifamily

0.00

7,286,895

42,042

5.28%

1-May-15

GMAC5C1B

Multifamily

0.00

7,250,000

31,900

5.62%

1-Jun-15

GMAC5C1A

Self Storage

0.00

7,136,554

44,732

5.14%

1-Oct-09

GMAC5C1A

Mixed Use

0.00

7,060,715

40,454

5.49%

1-Jun-15

GMAC5C1A

Office

0.00

6,678,380

38,113

5.54%

1-Apr-15

GMAC5C1A

Office

0.00

6,644,999

38,210

5.24%

1-Feb-15

GMAC5C1A

Office

0.00

6,525,519

36,405

5.16%

1-Mar-15

GMAC5C1A

Retail

0.00

6,250,000

26,875

5.82%

1-May-15

GMAC5C1A

Retail

0.00

6,094,132

36,075

5.63%

1-Apr-15

GMAC5C1A

Industrial

0.00

5,455,712

31,678

5.28%

1-May-15

GMAC5C1A

Office

0.00

5,161,019

28,811

5.66%

1-Jan-15

GMAC5C1A

Industrial

0.00

5,114,261

32,431

5.28%

1-May-15

GMAC5C1A

Retail

0.00

5,061,768

28,257

5.32%

1-Apr-15

GMAC5C1A

Retail

0.00

4,900,000

21,723

Page 26 of 33

determine such figures.

(1) Legend:

A. In Grace Period

B. Late Payment but < 1 month delinq

1. Delinquent 1 month
2. Delinquent 2 months

3. Delinquent 3+ months

4. Performing Matured Balloon

7. Foreclosure

9. REO

5. Non Performing Matured Ballon

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Loan Level Detail

Disclosure

Control #

Group

Property

Type

Maturity

Date

PFY

DSCR

Operating
Statement

Date

Geo.

Location

Ending

Principal

Balance

Note
Rate

Scheduled

P&I

Prepayment

Amount

Prepayment

Date

Loan

Status

Code (1)

Statement Date:

5.78%

1-May-15

GMAC5C1A

Retail

0.00

4,770,000

22,976

6.08%

1-Feb-25

GMAC5C1A

Industrial

0.00

4,452,481

32,808

5.30%

1-May-13

GMAC5C1B

Multifamily

0.00

4,500,000

19,875

5.45%

1-Jun-15

GMAC5C1A

Office

0.00

4,471,891

25,410

5.12%

1-May-15

GMAC5C1A

Retail

0.00

4,365,873

23,944

5.73%

1-Feb-10

GMAC5C1A

Lodging

0.00

3,940,431

25,116

5.71%

1-Jan-15

GMAC5C1A

Industrial

0.00

3,934,576

25,068

5.24%

1-Mar-15

GMAC5C1B

Multifamily

0.00

3,800,000

16,593

5.84%

1-May-15

GMAC5C1A

Retail

0.00

3,774,799

22,394

5.58%

1-Mar-25

GMAC5C1A

Retail

0.00

3,723,744

26,312

5.58%

1-May-10

GMAC5C1B

Multifamily

0.00

3,700,000

17,205

5.45%

1-Nov-14

GMAC5C1A

Retail

0.00

3,529,905

20,215

5.32%

1-May-15

GMAC5C1A

Office

0.00

3,473,987

19,479

5.74%

1-May-15

GMAC5C1A

Retail

0.00

3,365,940

21,369

5.41%

1-May-15

GMAC5C1A

Self Storage

0.00

3,314,508

20,392

5.71%

1-Apr-15

GMAC5C1A

Self Storage

0.00

3,224,277

18,884

5.78%

1-Apr-15

GMAC5C1B

Multifamily

0.00

3,125,444

18,443

5.88%

1-Jun-25

GMAC5C1A

Retail

0.00

2,764,048

19,867

5.35%

1-Feb-15

GMAC5C1A

Office

0.00

2,468,222

14,369

5.32%

1-Feb-15

GMAC5C1B

Multifamily

0.00

2,373,341

13,357

5.41%

1-Mar-15

GMAC5C1A

Retail

0.00

2,109,897

11,974

5.88%

1-Apr-15

GMAC5C1B

Multifamily

0.00

793,362

4,732

1,594,107,372

7,995,329

Page 27 of 33

determine such figures.

(1) Legend:

A. In Grace Period

B. Late Payment but < 1 month delinq

1. Delinquent 1 month
2. Delinquent 2 months

3. Delinquent 3+ months

4. Performing Matured Balloon

7. Foreclosure

9. REO

5. Non Performing Matured Ballon

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Specially Serviced (Part I) ~ Loan Detail (End of Period)

Disclosure

Control #

Servicing

Xfer Date

Balance

Note

Rate

Maturity

Date

Remaining

Property

Type

Geo.

Location

NOI

DSCR

NOI
Date

Schedule

Actual

Life

Statement Date:

Loan

Status

Code(1)

Page 28 of 33

(1) Legend:

A. P&I Adv - in Grace Period

B. P&I Adv - < one month delinq

1. P&I Adv - delinquent 1 month

2. P&I Adv - delinquent 2 months

3. P&I Adv - delinquent 3+ months

4. Mat. Balloon/Assumed P&I

7. Foreclosure

9. REO

5. Non Performing Mat. Balloon

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Specially Serviced Loan Detail (Part II) ~ Servicer Comments (End of Period)

Disclosure

Control #

Resolution

Strategy

Comments

Statement Date:

Page 29 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

Historical Collateral Level REO Report

Property

Type

Statement Date:

State

Actual

Balance

Scheduled

Balance

Recent

Appraisal

Value

Appraisal

Reduction

Amount

Date

Liquidated

Liquidation

Proceeds

Liquidation

Expenses

Realized

Loss

Disclosure

Control #

REO

Date

City

Appraisal

Date

ABN AMRO Acct: 722718.1

Page 30 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Modified Loan Detail

Disclosure

Control #

Modification

Date

Cutoff

Maturity

Date

Modification

Description

Modified

Maturity

Date

Statement Date:

Page 31 of 33

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Realized Loss Detail

Period

Disclosure

Control #

Appraisal

Date

Appraisal

Value

Beginning

Scheduled

Balance

Gross

Proceeds

Gross Proceeds

as a % of

Sched. Balance

Aggregate

Liquidation

Expenses *

Net

Liquidation

Proceeds

Net Proceeds

as a % of

Sched. Balance

Realized

Loss

Statement Date:

Current Total

Cumulative

Page 32 of 33

* Aggregate liquidation expenses also include outstanding P&I advances and unpaid servicing fees, unpaid trustee fees, etc..

GMAC Commercial Mortgage Securities, Inc.

Payment Date:
Prior Payment:
Next Payment:
Record Date:

12-Dec-05
12-Dec-05

10-Nov-05

10-Jan-06

30-Nov-05

Mortgage Pass-Through Certificates

Series 2005-C1

ABN AMRO Acct: 722718.1

Appraisal Reduction Detail

Disclosure

Control#

Appraisal

Red. Date

Scheduled

Balance

ASER

Note

Rate

Maturity

Date

Property

Type

Geographic

Location

Appraisal

Value Date

DSCR

Statement Date:

Remaining Term

Life

ARA

Amount

Current P&I

Advance

Page 33 of 33

Filing Compare · GMAC Commercial Mortgage Securities, Inc. Series 2005-C1 Trust