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                                                                    EXHIBIT 10.1

                       TWENTY-FIRST AMENDMENT TO THE THIRD
                        AMENDED AND RESTATED AGREEMENT OF
                  LIMITED PARTNERSHIP OF AIMCO PROPERTIES, L.P.

         This TWENTY-FIRST AMENDMENT TO THE THIRD AMENDED AND RESTATED AGREEMENT
OF LIMITED PARTNERSHIP OF AIMCO PROPERTIES, L.P., dated as of May 10, 2001 (this
"Amendment"), is being executed by AIMCO-GP, Inc., a Delaware corporation (the
"General Partner"), as the general partner of AIMCO Properties, L.P., a Delaware
limited partnership (the "Partnership"), pursuant to the authority conferred on
the General Partner by the Third Amended and Restated Agreement of Limited
Partnership of AIMCO Properties, L.P., dated as of July 29, 1994, as amended
and/or supplemented from time to time (the "Agreement"). Capitalized terms used,
but not otherwise defined herein, shall have the respective meanings ascribed
thereto in the Agreement.

         NOW, THEREFORE, in consideration of the foregoing, and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

         1. The definition of "Majority in Interest of the Limited Partners" in
Article I of the Agreement is amended to read in its entirety as follows:

                           "Majority in Interest of the Limited Partners" means
         Limited Partners (other than (i) the Special Limited Partner and (ii)
         any Limited Partner fifty percent (50%) or more of whose equity is
         owned, directly or indirectly, by (a) the General Partner or (b) any
         REIT as to which the General Partner is a "qualified REIT subsidiary"
         (within the meaning of Code Section 856(i)(2))) holding more than fifty
         percent (50%) of the outstanding Voting Units (as defined below) held
         by all Limited Partners (other than (i) the Special Limited Partner and
         (ii) any Limited Partner fifty percent (50%) or more of whose equity is
         owned, directly or indirectly, by (a) the General Partner or (b) any
         REIT as to which the General Partner is a "qualified REIT subsidiary"
         (within the meaning of Code Section 856(i)(2))). For purposes of this
         definition, "Voting Units" means Partnership Common Units, Class I High
         Performance Partnership Units and any other class of Partnership Units
         having the same voting or approval rights as Partnership Common Units.

         2. The Partnership Unit Designation of the Class I Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit Q to the Agreement) is hereby
amended to (i) remove from Section 2 the definition of "Majority in Interest of
the Limited Partners" and (ii) to remove the second sentence from Section 10.

         3. The Partnership Unit Designation of the Class Two Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit R to the Agreement) is hereby
amended to (i) remove from Section 2 the definition of "Majority in Interest of
the Limited Partners" and (ii) to remove the second sentence from Section 10.

         4. The Partnership Unit Designation of the Class Four Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit T to the Agreement) is hereby
amended to (i) remove from Section 2 the definition of "Majority in Interest of
the Limited Partners" and (ii) to remove the second sentence from Section 11.



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         5. The Partnership Unit Designation of the Class Three Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit U to the Agreement) is hereby
amended to (i) remove from Section 3 the definition of "Majority in Interest of
the Limited Partners" and (ii) to remove the second sentence from Section 10.

         6. The Partnership Unit Designation of the Class Five Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit V to the Agreement) is hereby
amended to (i) remove from Section 2 the definition of "Majority in Interest of
the Limited Partners" and (ii) to remove the second sentence from Section 9.

         7. The Partnership Unit Designation of the Class Six Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit X to the Agreement) is hereby
amended to (i) remove from Section 2 the definition of "Majority in Interest of
the Limited Partners" and (ii) to remove the second sentence from Section 11.

         8. The Partnership Unit Designation of the Class Seven Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit AA to the Agreement) is
hereby amended to (i) remove from Section 2 the definition of "Majority in
Interest of the Limited Partners" and (ii) to remove the second sentence from
Section 10.

         9. The Partnership Unit Designation of the Class Eight Partnership
Preferred Units of AIMCO Properties, L.P. (Exhibit BB to the Agreement) is
hereby amended to (i) remove from Section 2 the definition of "Majority in
Interest of the Limited Partners" and (ii) to remove the second sentence from
Section 9.

         10. Except as specifically amended hereby, the terms, covenants,
provisions and conditions of the Agreement shall remain unmodified and continue
in full force and effect and, except as amended hereby, all of the terms,
covenants, provisions and conditions of the Agreement are hereby ratified and
confirmed in all respects.


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         IN WITNESS WHEREOF, this Amendment has been executed as of the date
first written above.

                                            GENERAL PARTNER:

                                            AIMCO-GP, INC.



                                            By: /s/ JOEL F. BONDER
                                               --------------------------------
                                               Name:  Joel F. Bonder
                                               Title: Executive Vice President