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                                                                   EXHIBIT 10.11


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


         This TENTH AMENDMENT TO THE THIRD AMENDED AND RESTATED AGREEMENT OF
LIMITED PARTNERSHIP OF AIMCO PROPERTIES, L.P., dated as of December 21, 1999
(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 Section 7.3.C(7) of 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.

         WHEREAS, pursuant to Section 4.2.A of the Agreement, the General
Partner is authorized to determine the designations, preferences and relative,
participating, optional or other special rights, powers and duties of
Partnership Preferred Units.

         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 Agreement is hereby amended by the addition of a new exhibit,
entitled "Exhibit V," in the form attached hereto, which shall be attached to
and made a part of the Agreement.

         (2) 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.

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

                                            THE GENERAL PARTNER:

                                            AIMCO-GP, INC.



                                            By: /s/ PETER KOMPANIEZ
                                                --------------------------------
                                            Name:
                                            Title:



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                                    EXHIBIT V

                         PARTNERSHIP UNIT DESIGNATION OF
                  THE CLASS FIVE PARTNERSHIP PREFERRED UNITS OF
                             AIMCO PROPERTIES, L.P.


         1. NUMBER OF UNITS AND DESIGNATION.

         A class of Partnership Preferred Units is hereby designated as "Class
Five Partnership Preferred Units," and the number of Partnership Preferred Units
constituting such class shall be 150,000.

         2. DEFINITIONS.

         Capitalized terms used and not otherwise defined herein shall have the
meanings assigned thereto in the Third Amended and Restated Agreement of Limited
Partnership of AIMCO Properties, L.P. as amended, supplemented or restated from
time to time (the "Agreement"), as modified by this Partnership Unit Designation
and the defined terms used herein. For purposes of this Partnership Unit
Designation, the following terms shall have the respective meanings ascribed
below:

         "Assignee" shall mean a Person to whom one or more Class Five
Partnership Preferred Units have been Transferred in a manner permitted under
the Agreement, but who has not become a Substituted Limited Partner, and who has
the rights set forth in Section 11.5 of the Agreement.

         "Class Five Partnership Preferred Unit" shall mean a Partnership
Preferred Unit with the designations, preferences and relative, participating,
optional or other special rights, powers and duties as are set forth in this
Partnership Unit Designation.

         "Fair Market Value" shall mean, at any time and with respect to any
Class Five Partnership Preferred Units, the greater of (i) that portion of the
capital account balance of the holder of such Class Five Partnership Preferred
Units at that time attributable solely to such Class Five Partnership Preferred
Units, or (ii) zero.

         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 the
(a) 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 Partnership Common
Units, Class I High Performance Partnership Units, Class Four Partnership
Preferred Units, Class Five Partnership Preferred Units, and all other
outstanding classes of Partnership Units 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))).

         "Notice of Redemption" shall mean a Notice of Redemption in the form of
Annex I to this Partnership Unit Designation.


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         "Partnership" shall mean AIMCO Properties, L.P., a Delaware limited
partnership.

         "Transfer Agent" shall mean such transfer agent as may be designated by
the Partnership or its designee as the transfer agent for the Class Five
Partnership Preferred Units; provided, that if the Partnership has not
designated a transfer agent, then the Partnership shall act as the Transfer
Agent for the Class Five Partnership Preferred Units.

         3. CASH DISTRIBUTIONS.

                  At any time that the Partnership pays cash distributions to
holders of Partnership Common Units, the Partnership shall pay cash
distributions to holders of the Class Five Partnership Preferred Units in an
amount per Class Five Partnership Preferred Unit equal to the per unit
distribution on the Partnership Common Units; provided, that distributions upon
liquidation of the Partnership shall be made in accordance with Section 13.2 of
the Agreement. Holders of Class Five Partnership Preferred Units will not be
entitled to receive any other distributions. If a record date is established by
the General Partner for the payment of distributions in respect of Partnership
Common Units, the same date shall be the record date for payment of
distributions in respect of the Class Five Partnership Preferred Units. With
respect to the first distribution paid to holders of Class Five Partnership
Preferred Units after the initial issuance thereof, such distribution shall be
pro rated based on the portion of the period in respect of which such
distribution is paid that such that such Class Five Partnership Preferred Units
were outstanding.

         4. REDEMPTION.

                  (a) The Class Five Partnership Preferred Units may be redeemed
at the option of the Partnership at any time at a redemption price payable in
cash equal to the Fair Market Value of such Class Five Partnership Preferred
Units.

                  (b) The redemption date shall be selected by the Partnership,
shall be specified in a notice of redemption, and shall be not less than 5 days
nor more than 60 days after the date notice of redemption is sent by the
Partnership.

                  (c) If the Partnership shall redeem Class Five Partnership
Preferred Units, notice of such redemption shall be given to each holder of
record of the Class Five Partnership Preferred Units to be redeemed. Such notice
shall be provided by first class mail, postage prepaid, at such holder's address
as the same appears on the records of the Partnership. Neither the failure to
mail any notice required by this paragraph (c), nor any defect therein or in the
mailing thereof to any particular holder, shall affect the sufficiency of the
notice or the validity of the proceedings for redemption with respect to the
other holders. Any notice which has been mailed in the manner herein provided
shall be conclusively presumed to have been duly given on the date mailed
whether or not the holder receives the notice. Each such notice shall state, as
appropriate: (i) the redemption date; (ii) the place or places at which
certificates for such shares are to be surrendered for cash; and (iii) the
redemption price payable on such redemption date. Notice having been mailed as
aforesaid, from and after the redemption date (unless the Partnership shall fail
to make available the amount of cash necessary to effect such redemption), (i)
such Class Five Partnership Preferred Units shall no longer be deemed to be
outstanding, and (ii) all rights of the holders thereof as holders of Class Five
Partnership Preferred Units shall cease except the right to receive the cash
payable upon such redemption, without interest thereon, upon surrender of their
certificates if so required. As promptly as practicable after the surrender in
accordance with such notice of the certificates for any


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such Class Five Partnership Preferred Units to be so redeemed (properly endorsed
or assigned for transfer, if the Partnership shall so require and the notice
shall so state), such certificates shall be exchanged for cash (without interest
thereon) for which such shares have been redeemed in accordance with such
notice.

         5. CONVERSION.

                  (a) Subject to and upon compliance with the provisions of this
Section 5, on or after December 21, 2000, a holder of Class Five Partnership
Preferred Units shall have the right, at such holder's option, to convert such
units, in whole or in part, into the number of Partnership Common Units obtained
by dividing (i) the Fair Market Value of the Class Five Partnership Preferred
Units converted, by (ii) the value of a REIT Share (assuming, for such purpose,
that the Valuation Date is the date of conversion of such units). In order to
exercise the conversion right, the holder of each Class Five Partnership
Preferred Unit to be converted shall surrender the certificate representing such
unit, duly endorsed or assigned to the Partnership or in blank at the office of
the Transfer Agent, accompanied by written notice to the Partnership that the
holder thereof elects to covert such Class Five Partnership Preferred Unit.

                  (b) (i) Unless the Partnership Common Units issuable on
conversion are to be issued in the same name as the name in which such Class
Five Partnership Preferred Units are registered, each such unit surrendered
following conversion shall be accompanied by instruments of transfer, in form
satisfactory to the Partnership, duly executed by the holder or such holder's
duly authorized representa tive, and an amount sufficient to pay any transfer or
similar tax (or evidence reasonably satisfactory to the Partnership
demonstrating that such taxes have been paid).

                           (ii) As promptly as practicable after the surrender
of certificates for Class Five Partnership Preferred Units as aforesaid, and in
any event no later than three business days after the date of such surrender,
the Partnership shall issue and deliver at such office to such holder, or send
on such holders' written order, a certificate or certificates for the number of
full Partnership Common Units issuable upon the conversion of such Class Five
Partnership Preferred Units in accordance with the provisions of this Section 5,
and any fractional interest in respect of a Partnership Common Unit arising upon
such conversion shall be settled as provided in paragraph (c) of this Section 5.

                           (iii) Each conversion shall be deemed to have been
effected immediately prior to the close of business on the date on which the
certificates for Class Five Partnership Preferred Units shall have been
surrendered to the Partnership for conversion as provided in paragraph (a) of
this Section 5; and the person or persons in whose name or names any certificate
or certificates for Partnership Common Units shall be issuable upon such
conversion shall be deemed to have become the holder or holders of record of the
units represented thereby at such time on such date unless the transfer books of
the Partnership shall be closed on that date, in which event such person or
persons shall be deemed to become such holder or holders of record at the close
of business on the next succeeding day on which such transfer books are open.

                  (c) No fractional Partnership Common Units or scrip
representing fractions of a Partnership Common Unit shall be issued upon
conversion of the Class Five Partnership Preferred Units. Instead of any
fractional interest in a Partnership Common Unit that would otherwise be
deliverable upon the conversion of Class Five Partnership Preferred Units, the
Partnership shall pay to the holder of such


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units an amount of cash equal to the Fair Market Value of such fractional
interest as of the date of conversion. If more than one of any holder's units
shall be converted at one time, the number of full Partnership Common Units
issuable upon conversion thereof shall be computed on the basis of the aggregate
number of Class Five Partnership Preferred Units so converted.

                  (d) If the Partnership shall be a party to any transaction
(including with limitation a merger, consolidation, statutory exchange, sale of
all or substantially all of the Partnership's assets or recapitalization of the
Partnership Common Units, but excluding any transaction as to which a change in
the Adjustment Factor would be effected) (each of the foregoing being referred
to herein as a "Transaction"), in each case, as a result of which Partnership
Common Units shall be converted into the right to receive securities or other
property (including cash or any combination thereof), each Class Five
Partnership Preferred Unit which is not converted into the right to receive
securities or other property in connection with such Transaction shall thereupon
be convertible into the kind and amount of securities and other property
(including cash or any combination thereof) receivable upon such consummation by
a holder of that number of Partnership Common Units into which a Class Five
Partnership Preferred Unit was convertible immediately prior to such
Transaction. The Partnership shall not be a party to any Transaction unless the
terms of such Transaction are consistent with the provisions of this paragraph
(d), and it shall not consent or agree to the occurrence of any Transaction
until the Partnership has entered into an agreement with the successor or
purchasing entity, as the case may be, for the benefit of the holders of the
Class Five Partnership Preferred Units that will contain provisions enabling the
holders of Class Five Partnership Preferred Units that remain outstanding after
such Transaction to convert into the consideration received by holders of
Partnership Common Units at the conversion price in effect immediately prior to
such Transaction. The provisions of this paragraph (d) shall apply to successive
Transactions.

                  (e) The Partnership will pay any and all documentary stamp or
similar issue or transfer taxes payable in respect of the issue or delivery of
Partnership Common Units or other securities or property on conversion of Class
Five Partnership Preferred Units pursuant hereto; provided, however, that the
Partnership shall not be required to pay any tax that may be payable in respect
of any transfer involved in the issue or delivery of Partnership Common Units or
other securities or property in a name other than that of the holder of the
Class Five Partnership Preferred Units to be converted, and no such issue or
delivery shall be made unless and until the person requesting such issue or
delivery has paid to the Partnership the amount of any such tax or established,
to the reasonable satisfaction of the Partnership, that such tax has been paid.

         6. STATUS OF REACQUIRED UNITS.

                  All Class Five Partnership Preferred Units which shall have
been issued and reacquired in any manner by the Partnership shall be deemed
cancelled and no longer outstanding.

         7. GENERAL.

                  The ownership of the Class Five Partnership Preferred Units
shall be evidenced by one or more certificates in the form of Annex II hereto.
The General Partner shall amend Exhibit A to the Agreement from time to time to
the extent necessary to reflect accurately the issuance of, and subsequent
redemption, or any other event having an effect on the ownership of, the Class
Five Partnership Preferred Units.


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         8. ALLOCATIONS OF INCOME AND LOSS; CAPITAL ACCOUNTS.

                  Upon initial issuance, the capital account balance
attributable to the Class Five Partnership Preferred Units shall be zero.
Thereafter, for each Fiscal Year, the Class Five Partnership Preferred Units
shall be allocated a portion of the Net Income and Net Loss of the Partnership
equal to the portion of the Net Income and Net Loss of the Partnership that
would be allocated to such Class Five Partnership Preferred Units pursuant to
Article 6 of the Agreement if the Class Five Partnership Preferred Units were
Partnership Common Units. In addition, (i) not more than 60 days prior to a
redemption of Class Five Partnership Preferred Units pursuant to Section 4
hereof and (ii) at any time after December 21, 2001, upon (x) a sale of
substantially all of the assets of the Partnership or a liquidation,
dissolution, or winding up of the Partnership or (y) in the event the Gross
Asset Value of any Partnership Asset is adjusted pursuant to subsection (b) or
(c) of the definition of "Gross Asset Value" in the Agreement, to the extent
possible, the Partnership shall first allocate Partnership gain (and, to the
extent necessary, gross income) among the Class Five Partnership Preferred Units
(the "Special Allocation") in an amount equal to that necessary to permit each
Class Five Partnership Preferred Unit to receive, upon a liquidation,
dissolution, or winding up of the Partnership pursuant to Section 13.2 of the
Agreement, an amount of assets of the Partnership equal to the amount of assets
that would be receivable with respect to a Partnership Common Unit, as
determined on a per unit basis. Notwithstanding the foregoing, the Class Five
Partnership Preferred Units shall not be entitled to receive, and shall not
receive, the Special Allocation unless and until the Class I High Performance
Partnership Units have been allocated the full amount of Partnership income and
gain required under Section 5 of the Partnership Unit Designation for the Class
I High Performance Partnership Units.

         9. VOTING RIGHTS

                  Except as otherwise required by applicable law or in the
Agreement, the holders of the Class Five Partnership Preferred Units will have
the same voting rights as holders of the Partnership Common Units. As long as
any Class Five Partnership Preferred Units are outstanding, for purposes of
determining the Consent of Limited Partners under the Agreement, the "Majority
In Interest of the Limited Partners" shall have the meaning set forth in Section
2 hereof. As long as any Class Five Partnership Preferred Units are outstanding,
in addition to any other vote or consent of partners required by law or by the
Agreement, the affirmative vote or consent of holders of at least 50% of the
outstanding Class Five Partnership Preferred Units will be necessary for
effecting any amendment of any of the provisions of the Partnership Unit
Designation of the Class Five Partnership Preferred Units that materially and
adversely affects the rights or preferences of the holders of the Class Five
Partnership Preferred Units. The creation or issuance of any class or series of
Partnership Units, including, without limitation, any Partnership Units that may
have rights junior to, on a parity with, or senior or superior to the Class Five
Partnership Preferred Units, will not be deemed to materially and adversely
affect the rights or preferences of the holders of the Class Five Partnership
Preferred Units. With respect to the exercise of the above-described voting
rights, each Class Five Partnership Preferred Unit will have one (1) vote per
Class Five Partnership Preferred Unit.

         10. RESTRICTIONS ON TRANSFER.

                  Class Five Partnership Preferred Units are subject to the same
restrictions on transfer applicable to Partnership Common Units, as set forth in
the Agreement.


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                                                                         ANNEX I
                                                                    TO EXHIBIT V

                            FORM OF UNIT CERTIFICATE
                                       OF
                     CLASS FIVE PARTNERSHIP PREFERRED UNITS

THE SECURITY EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE "ACT"), OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT
BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH
REGISTRATION, UNLESS THE TRANSFEROR DELIVERS TO THE PARTNERSHIP AN OPINION OF
COUNSEL SATISFACTORY TO THE PARTNERSHIP, IN FORM AND SUBSTANCE SATISFACTORY TO
THE PARTNERSHIP, TO THE EFFECT THAT THE PROPOSED SALE, TRANSFER OR OTHER
DISPOSITION MAY BE EFFECTED WITHOUT REGISTRATION UNDER THE ACT AND UNDER
APPLICABLE STATE SECURITIES OR "BLUE SKY" LAWS. IN ADDITION, THE LIMITED
PARTNERSHIP INTEREST EVIDENCED BY THIS CERTIFICATE MAY BE SOLD OR OTHERWISE
TRANSFERRED ONLY IN COMPLIANCE WITH THE RESTRICTIONS ON TRANSFER SET FORTH IN
THE AGREEMENT OF LIMITED PARTNERSHIP OF AIMCO PROPERTIES, L.P., DATED AS OF JULY
29, 1994, AS IT MAY BE AMENDED AND/OR SUPPLEMENTED FROM TIME TO TIME, A COPY OF
WHICH MAY BE OBTAINED FROM AIMCO-GP, INC, THE GENERAL PARTNER, AT ITS PRINCIPAL
EXECUTIVE OFFICE.

                                                    Certificate Number
                                                                       ---------

                             AIMCO PROPERTIES, L.P.
                 FORMED UNDER THE LAWS OF THE STATE OF DELAWARE

This certifies that
                    ------------------------------------------------------------

is the owner of
                ----------------------------------------------------------------

                     CLASS FIVE PARTNERSHIP PREFERRED UNITS
                                       OF
                             AIMCO PROPERTIES, L.P.,

transferable on the books of the Partnership in person or by duly authorized
attorney on the surrender of this Certificate properly endorsed. This
Certificate and the Class Five Partnership Preferred Units represented hereby
are issued and shall be held subject to all of the provisions of the Agreement
of Limited Partnership of AIMCO Properties, L.P., as the same may be amended
and/or supplemented from time to time.

IN WITNESS WHEREOF, the undersigned has signed this Certificate.

Dated:                                  By:
       --------                             ------------------------------------
                                        Name:
                                        Title:


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                                   ASSIGNMENT




         For Value Received, ____________________________ hereby sells, assigns
and transfers unto _____________________________________________________________
______________________________________________ Class Five Partnership Preferred
Unit(s) represented by the within Certificate, and does hereby irrevocably
constitute and appoint the General Partner of AIMCO Properties, L.P. as its
Attorney to transfer said Class Five Partnership Preferred Unit(s) on the books
of AIMCO Properties, L.P. with full power of substitution in the premises.


Dated:
       ---------------------

                                   By:
                                       -----------------------------------------
                                                      Name:


                                   Signature Guaranteed by:
                                                            --------------------


NOTICE: THE SIGNATURE OF THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME(S) AS
WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR WITHOUT ALTERATION
OR ENLARGEMENT OR ANY CHANGE WHATEVER.

THE SIGNATURE SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION, (Banks,
Stockbrokers, Savings and Loan Associations and Credit Unions), WITH MEMBERSHIP
IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM PURSUANT TO SEC RULE
17Ad-15.


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