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                                                                 EXHIBIT 10.12

                          LIMITED PARTNERSHIP AGREEMENT
                                       OF
                            CAC V LIMITED PARTNERSHIP

     This LIMITED PARTNERSHIP AGREEMENT (the "Partnership Agreement") is made as
of June 8, 2001 by and between CAC V Special General, Inc., a Virginia
corporation, the general partner ("General Partner"), and CAC V Special Limited,
Inc., a Virginia corporation, the limited partner ("Limited Partner").

                                  INTRODUCTION

     A.   The General Partner and the Limited Partner (collectively, the
"Partners") have formed a limited partnership (the "Partnership") pursuant to
the provisions of the Virginia Revised Uniform Limited Partnership Act (the
"Act"), effective June 8, 2001. The General Partner and the Limited Partner are
each wholly-owned subsidiaries of Cornerstone Acquisition Company, a Virginia
corporation.

     B.   The rights, duties and obligations of the Partners shall be governed
by the Act except as otherwise provided in this Partnership Agreement. The term
"Person," as used herein, means an individual or an entity.


                                    ARTICLE I
                             ORGANIZATIONAL MATTERS

     1.1  Name. The name of the Partnership is CAC V Limited Partnership. The
Partnership may trade or transact business under such other names as may be
selected by the General Partner.

     1.2  Purpose. The Notwithstanding any provision hereof to the contrary,
the following shall govern: The nature of the Partnership's business, and of the
purposes to be conducted and promoted by the Partnership, are limited solely to
the following activities:

          (a)  To own, hold, sell, assign, transfer, operate, lease, mortgage,
pledge and otherwise deal with those certain parcels of real property listed on
Exhibit A hereto, together with all improvements located thereon (collectively,
---------
the "Properties");

          (b)  To exercise all powers that are enumerated in the Act and are
necessary or convenient to the conduct, promotion or attainment of the business
or purposes of the Partnership as set forth herein.

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     1.3  Filings.

          (a)  The Partnership has filed a certificate of limited partnership
with the State Corporation Commission of Virginia pursuant to Section 50-73.11
of the Code of Virginia (the "Certificate").

          (b)  The Certificate designates 306 East Main Street, Richmond,
Virginia 23219 as the office where records of the Partnership are kept (the
"Principal Office"). The Certificate designates Martin B. Richards, Esquire, as
the registered agent at the following registered office: c/o McGuireWoods LLP,
One James Center, 901 East Cary Street, Richmond, Virginia 23219.


                                   ARTICLE II

          MANAGEMENT, PROHIBITED ACTIVITIES AND SEPARATENESS COVENANTS

     2.1  The General Partner. The General Partner shall have the sole and
exclusive right, duty and power to manage the business of the Partnership,
including, without limitation, the right and power to:

          (a)  acquire, hold, sell, maintain, encumber, improve, develop or
lease the Partnership's property, whether real or personal, and any interest
therein on such terms and conditions as the General Partner deems advisable.

          (b)  borrow money on behalf of the Partnership, secure any such
borrowings with assets of the Partnership, and repay the same at any time or
from time to time;

          (c)  establish investment accounts for the Partnership and deposit and
withdraw funds in or from such accounts;

          (d)  assign, compromise or release any claim of, or debt due to, the
Partnership;

          (e)  institute and defend actions at law or in equity on behalf of the
Partnership and consent to arbitrate any disputes or controversies of the
Partnership;

          (f)  engage and retain accountants, lawyers and other professionals to
perform services for the Partnership, and purchase such goods and other services
as may be required to conduct the business of the Partnership; and

          (g)  enter into such contracts and perform such other acts as may be
necessary to further the business of the Partnership.

                                       -2-

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          2.2.    Certain Prohibited Activities. Notwithstanding any provision
hereof to the contrary, the following shall govern:

                  (a)  The indebtedness of the Partnership shall consist only of
a first lien mortgage on the Properties arising from financing by First Union
National Bank (the "Mortgage"), any other indebtedness permitted under the
Mortgage, and normal trade accounts payable in the ordinary course of business.
For so long as any obligation secured by the Mortgage remains outstanding and
not paid in full, the Partnership shall not incur, assume, or guaranty any
indebtedness not permitted hereunder.

                  (b)  The Partnership shall not consolidate or merge with or
into any other entity, or convey or transfer its properties and assets
substantially as an entirety to any entity, unless:

                       (i)  the entity that is formed upon such consolidation,
that survives such merger (if other than the Partnership), or that acquires by
conveyance or transfer the properties and assets of the Partnership
substantially as an entirety, shall: (A) be organized and existing under the
laws of the United States of America or any State or the District of Columbia,
(B) include in its organizational documents the same limitations set forth in
this Article II and in Section 2.3 hereof (Separateness Covenants), and (C)
expressly assume the due and timely performance of the Partnership's obligations
; and

                       (ii) immediately after giving effect to such transaction,
no default or event of default will have occurred under any agreement to which
the Partnership is a party.

                  (c)  For so long as any obligation secured by the Mortgage
remains outstanding and not paid in full, the Partnership shall not voluntarily
commence a case with respect to itself, as debtor, under the Federal Bankruptcy
Code or any similar federal or state statute without the unanimous consent of
the Partners. For so long as any obligation secured by the Mortgage remains
outstanding and not paid in full, no material amendment to this Partnership
Agreement may be made without the prior approval of the mortgagee holding the
Mortgage.

          2.3     Separateness Covenants. Notwithstanding any provision hereof
to the contrary, the following shall govern: For so long as any obligation
secured by the Mortgage remains outstanding and not paid in full, in order to
preserve and ensure the Partnership's separate and distinct identity, in
addition to the other provisions set forth in this Partnership Agreement, the
Partnership shall conduct its affairs in accordance with the following
provisions:

                  (a)  It shall establish and maintain an office through which
its business shall be conducted separate and apart from those of its Partners
and any affiliate and it shall allocate fairly and reasonably any overhead for
shared office space.

                  (b)  It shall maintain separate records and books of account
from those of its Partners and any affiliate.

                                       -3-

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               (c)  All actions by the Partnership shall be authorized by the
General Partner, who shall observe all necessary formalities in connection with
such authorization.

               (d)  It shall not commingle assets with those of its Partners or
any affiliate.

               (e)  It shall conduct its own business in its own name.

               (f)  It shall maintain financial statements separate from its
Partners and any affiliate.

               (g)  It shall pay any liabilities out of its own funds, including
salaries of any employees, not funds of its Partners or any affiliate.

               (h)  It shall maintain an arm's length relationship with its
Partners and any affiliate.

               (i)  It shall not guarantee or become obligated for the debts of
any other person or entity (including, without limitation, its Partners or any
affiliate) and shall not hold out its credit as being available to satisfy the
obligations of others.

               (j)  It shall use stationery, invoices and checks separate from
its Partners and any affiliate.

               (k)  It shall not pledge its assets for the benefit of any other
person or entity (including, without limitation, its Partners or any affiliate).

               (l)  It shall hold itself out as an entity separate from its
Partners and any affiliate.

               (m)  It shall not make any loans or advances to any third party
(including, without limitation, any affiliate).

               (n)  It shall comply with its obligations under the agreements
 and instruments evidencing the Mortgage.

          2.4  Definitions. For purpose of this Article II, the following terms
shall have the indicated meanings:

               (a)  "affiliate" means, with respect to a specified person or
entity:

                    (i)  any person or entity directly or indirectly owning,
controlling or holding with power to vote ten percent (10%) or more of the
outstanding voting securities or interests of the specified entity;

                    (ii) any person or entity ten percent (10%) or more of whose
outstanding voting securities or interests are directly or indirectly owned,
controlled or held with power to vote by the specified person or entity;

                                       -4-

<PAGE>

               (iii) any person or entity directly or indirectly controlling,
controlled by or under common control with the specified person or entity;

               (iv)   any officer, director or partner of the specified person
or entity;

               (v)    if the specified person or entity is an officer, director
or partner, any company for which the specified person or entity acts in any
such capacity; and

               (vi)   any close relative or spouse of the specified person.

          (b)  "control" means the possession, directly or indirectly, of the
power to direct or cause the direction of the management and policies of a
person or entity, whether through ownership of voting securities, by contract or
otherwise.

          (c)  "person or entity" means any individual, corporation,
partnership, limited liability company, joint venture, association, joint stock
company, trust (including any beneficiary thereof), unincorporated organization,
government or any agency or political subdivision thereof.

                                   ARTICLE III
                                LIMITED PARTNERS

     3.1  Participation in Management. The Limited Partner shall not participate
in the management or control of the business of the Partnership, and shall have
no power to sign for or bind the Partnership.

                                   ARTICLE IV
                   CAPITAL; PROFITS AND LOSSES; DISTRIBUTIONS

     4.1  Capital Contributions. Each of the Partners has contributed to the
capital of the Partnership the property set forth on Exhibit B hereto. The
                                                     ---------
Partners shall not be required to make any additional capital contributions
except as required by law, but the Partners may make such additional
contributions of cash or property as they may mutually agree. No Partner shall
have any right to require the return of all or any part of its capital, or to
receive interest with respect thereto.

     4.2  Capital Accounts. A separate capital account ("Capital Account") shall
be maintained for each Partner. The value of each Capital Account shall be the
sum of the cash contributions to the account, the agreed upon value of
contributions of property to the account and the share of Partnership profits
allocated to the account, less all distributions made from the account and the
share of Partnership losses allocated to the account.

     4.3  Profits and Losses. The net profits and net losses of the Partnership
for any period (except for the profits and losses upon dissolution) shall be
credited or charged to the

                                       -5-

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Capital Accounts of the Partners in the percentages set forth on Exhibit B under
                                                                 ---------
the heading "Partners Percentages," as the same may be amended from time to time
(the "Partners Percentages").

          4.4  Distributions. Any cash which, in the opinion of the General
Partner, is not reasonably required for the operation of the business of the
Partnership or for Partnership reserves (other than amounts distributed upon
dissolution) shall be distributed to the Partners in accordance with the
Partners Percentages not less frequently than each calendar quarter. Other
distributions of assets may be made form time to time in the same manner.

          4.5  Loans. A loan by a Partner to the Partnership shall not be
considered a capital contribution and shall be repaid as debt of the
Partnership.


                                    ARTICLE V
                                 INDEMNIFICATION

          5.1  Requirement. The Partnership shall indemnify each Partner, and
each director and officer of a Partner (an "Indemnified Person"), against any
and all liabilities and expenses (including but not limited to reasonable legal
fees and costs) arising directly or indirectly from any action, suit or
proceeding, whether civil, criminal, administrative, arbitrative or
investigative, and whether formal or informal, that is brought or threatened
against an Indemnified Person solely because such Indemnified Person served as a
Partner or as a director or officer of a Partner, or served at the request of
the Partnership as a fiduciary for an employee benefit plan or other plan
related to the business of the Partnership. Notwithstanding the foregoing, the
Partnership shall not be required to indemnify a Partner, or a director or
officer of a Partner, against any liabilities or expenses arising from any
breach of this Partnership Agreement, willful misconduct or knowing violation of
law.

          5.2  Related Actions. The Partnership shall promptly make advances or
reimbursements for reasonable expenses (including but not limited to reasonable
legal fees and costs) incurred by a Partner, or a director or officer of a
Partner, claiming indemnification under this Article unless it has been
determined that such Partner, director or officer is not entitled to
indemnification. Advances or reimbursements made prior to such determination
shall be conditioned upon the Partnership's receipt of a written undertaking by
the Partner, director or officer claiming indemnification to repay the amount of
such advances or reimbursements if it is ultimately determined that such
Partner, director or officer is not entitled to indemnification.

          5.3  Mandatory Subordination. Notwithstanding any provision hereof to
the contrary, the following shall govern: Any indemnification shall be fully
subordinated to any obligations respecting the Properties and shall not
constitute a claim against the Partnership in the event that cash flow is
insufficient to pay such obligations.

                                       -6-

<PAGE>
                                   ARTICLE VI
                              EVENTS OF DISSOLUTION

          6.1  Events of Dissolution.  The Partnership shall only be dissolved:

               (a)  upon the election of the General Partner;

               (b)  at such time as there is no General Partner serving unless,
within ninety (90) days, the Limited Partner consents to continue the business
of the Partnership and appoints one or more General Partners;

               (c)  upon automatic cancellation of the certificate of limited
partnership for failure to pay annual registration fees, unless steps are taken
promptly to obtain reinstatement; or

               (d)   by judicial decree.


                                   ARTICLE VII
                     DISSOLUTION, WINDING UP AND TERMINATION

          7.1 General. Upon dissolution without continuation, the business of
the Partnership shall be wound up by the General Partner or, if there is no
General Partner, by a representative designated by the Limited Partner (either
of which or whom is hereinafter referred to as the "Liquidating
Representative").  The Liquidating Representative shall proceed with reasonable
promptness to  liquidate the business and assets of the Partnership and may
determine whether,  and to which Partners, properties should be distributed in
kind. Partnership  assets shall be distributed in the following order:

               (a) to creditors of the Partnership, including Partners who are
creditors, in the order of priority provided by law or contract;

               (b) to the creation of such reserves for contingencies as the
Liquidating Representative may deem necessary or advisable;

               (c) to the Limited Partner to the extent of its contribution to
capital;

               (d) to the General Partner to the extent of its contribution to
capital;

               (e) to the Partners, General and Limited, according to their
Capital Account balances, after all adjustments.

                                       -7-

<PAGE>

                                  ARTICLE VIII
                                  MISCELLANEOUS

          8.1  Books of Account and Records. The Partnership shall keep
complete books of account at the Principal Office and such books shall be open
to examination by the Partners and the authorized representatives of each of
them during normal business hours. The books shall be kept on a cash or accrual
basis, as determined by the General Partner.

          8.2  Tax Compliance. Notwithstanding anything to the contrary
contained 704 of the Internal Revenue Code of 1986, as amended (the "Code"),
and the Regulations thereunder. The General Partner shall be the "Tax Matters
Partner" required by the Code.

          8.3  Power of Attorney. The Limited Partner hereby appoints the
General Partner as its attorney-in-fact, or agent, to execute, acknowledge,
deliver and file in its name any document required by law to be filed by the
Partnership or the Limited Partner with any governmental body or agency. Any
such appointment is a special power, coupled with an interest, and shall remain
in effect as long as the Partner granting it has any interest in the
Partnership or remains responsible for any obligations under this Partnership
Agreement.

          8.4  Counterparts. This Partnership Agreement may be executed in
counterparts, each of which shall be deemed an original but which together shall
constitute one and the same instrument.

          8.5  Amendments. This Partnership Agreement may be amended only with
the written consent of the General Partner and the Limited Partner.

          8.6  Third Parties; Successors and Assigns. The agreements contained
herein are for the benefit of the parties hereto and their permitted successors
and assigns and are not for the benefit of any third parties, such as, without
limitation, creditors of the Partnership.

          8.7  Headings. The section headings in this Partnership Agreement are
included for convenience only and shall not affect the interpretation of this
Partnership Agreement.

          8.8  Interpretation. This Partnership Agreement is executed and
delivered in the Commonwealth of Virginia and shall be construed and enforced in
accordance with its laws, without regard to any choice of law rules to the
contrary.

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<PAGE>

WITNESS the following signatures:


GENERAL PARTNER:                            CAC V Special General, Inc.
---------------



                                            By:   /s/ Stanley J. Olander, Jr.
                                                  -----------------------------
                                                     Stanley J. Olander, Jr.,
                                                     Vice President




LIMITED PARTNER:                            CAC V Special Limited, Inc.
---------------



                                            By:   /s/ Stanley J. Olander, Jr.
                                                  ----------------------------
                                                    Stanley J. Olander, Jr.,
                                                    Vice President

                                       -9-

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                                    Exhibit A
                              (List of Properties)

The Properties consist of those real properties, together with all improvements
thereon, that are located at the following addresses:

         Cottonwood Crossing Apartments
         2103 Cottonwood Club
         Arlington, Texas  76010

         Main Park Apartments
         1303 S. Main Street
         Duncanville, Texas  75137

         Paces Cove Apartments
         13100 Pandora Drive
         Dallas, Texas  75238

         WildWood Apartments
         200 Bear Creek Drive
         Euless, Texas  76039


                                       -10-

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                                    Exhibit B
                             (Capital Contributions)

<TABLE>
<CAPTION>
                           Name and                           Capital                   Partners
                           Business Address                   Contributions             Percentages
                           ----------------                   -------------             -----------
<S>                        <C>                                <C>                        <C>
General Partner:           CAC V Special General, Inc.        $ 1.00                     1%
                           306 East Main Street
                           Richmond, Virginia  23219

Limited Partner:           CAC V Special Limited, Inc.        $99.00                    99%
                           306 East Main Street
                           Richmond, Virginia  23219

</TABLE>

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