ACKNOWLEDGMENT AND AGREEMENT
                    TO TENDER UNITS OF LIMITED PARTNERSHIP IN
       WINTHROP GROWTH INVESTORS 1 LIMITED PARTNERSHIP (THE "PARTNERSHIP")
                        PURSUANT TO AN OFFER TO PURCHASE
                      DATED MAY 9, 2003 (THE "OFFER DATE")
                                       BY
                             AIMCO PROPERTIES, L.P.

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  FOR INFORMATION OR ASSISTANCE IN CONNECTION WITH THE OFFER OR THE COMPLETION
 OF THIS ACKNOWLEDGMENT AND AGREEMENT, PLEASE CONTACT THE INFORMATION AGENT AT
                                (800) 461-2657.
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            WHEN COMPLETING THIS ACKNOWLEDGMENT AND AGREEMENT, PLEASE
            REFER TO THE INSTRUCTIONS SET FORTH ON THE LAST PAGE OF
                        THIS ACKNOWLEDGMENT AND AGREEMENT

The undersigned hereby agrees as set forth under "ACKNOWLEDGMENT AND AGREEMENT"
below.

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1                                SIGNATURE BOX
                (SEE INSTRUCTION 2 IN THE LETTER OF TRANSMITTAL)
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         Please sign exactly as your name is printed in Box 2 below. For joint
owners, each joint owner must sign. (See Instruction 2 in the Letter of
Transmittal).

        X
          ----------------------------------------------------------------------
                                   (Signature of Owner)

        X
          ----------------------------------------------------------------------
                                  (Signature of Joint Owner)

        Name and Capacity (if other than individuals):
                                                      --------------------------
        Title:
               -----------------------------------------------------------------
        Address:
                 ---------------------------------------------------------------

       -------------------------------------------------------------------------
       (City)                              (State)                   (Zip)

       Area Code and Telephone No. (Day):
                                          --------------------------------------
                               (Evening):
                                          --------------------------------------

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<Table>
<Caption>

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2                         DESCRIPTION OF UNITS TENDERED
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Name(s), Address(es), Number of Units Owned and Tax Identification Number of
Registered Holder(s). (Please indicate changes or corrections to the name,        Total Number of Units Tendered
address, number of units owned and tax identification number printed below.)      (#)
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[ ] Check box if the units have been tendered in another tender offer.

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</Table>






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   3                    SIGNATURE GUARANTEE (IF REQUIRED)
                (SEE INSTRUCTION 2 IN THE LETTER OF TRANSMITTAL)
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YOU DO NOT NEED TO HAVE YOUR SIGNATURE GUARANTEED UNLESS YOU ARE A TRUSTEE,
EXECUTOR, ADMINISTRATOR, GUARDIAN, ATTORNEY-IN-FACT, OFFICER OF A CORPORATION OR
OTHER PERSON ACTING IN A FIDUCIARY OR REPRESENTATIVE CAPACITY.

Name and Address of Eligible Institution:
                                          --------------------------------------

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Authorized Signature: X
                        --------------------------------------------------------
Name:                       Title:                             Date:
     ---------------------         ---------------------------       -----------

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4                          SPECIAL PAYMENT INSTRUCTIONS
           (SEE INSTRUCTIONS 2, 7 AND 8 IN THE LETTER OF TRANSMITTAL)
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To be completed ONLY if the consideration for the purchase price of Units
accepted for payment is to be issued in the name of someone other than the
Signatory.

Issue consideration to:

Name
     ---------------------------------------------------------------------------
                               (Please Type or Print)

Address
        ------------------------------------------------------------------------

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- --------------------------------------------------------------------------------
                                (Include Zip Code)

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                   (TAX IDENTIFICATION OR SOCIAL SECURITY NO.)

                         (See Substitute Form W-9 below)
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5                         SPECIAL DELIVERY INSTRUCTIONS
                   (SEE INSTRUCTIONS 2, 7 AND 8 IN THE LETTER
                                 OF TRANSMITTAL)
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To be completed ONLY if the consideration for the purchase price of Units
accepted for payment is to be sent to someone other than the Signatory or to the
Signatory at an address other than that shown in Box 2 above.

Mail consideration to:

Name
     ---------------------------------------------------------------------------
                               (Please Type or Print)

Address
        ------------------------------------------------------------------------

- --------------------------------------------------------------------------------

- --------------------------------------------------------------------------------
                               (Include Zip Code)

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6                             SUBSTITUTE FORM W-9
            (SEE INSTRUCTION 4 - BOX 6 OF THE LETTER OF TRANSMITTAL)
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Under penalties of perjury, the Signatory certifies that: (1) the number shown
on this form is the unitholder's correct Taxpayer Identification No. ("TIN") or
the unitholder has applied for a TIN; and (2) the unitholder is not subject to
backup withholding either because the unitholder : (a) is exempt for backup
withholding; (b) has not been notified by the Internal Revenue Service ("IRS")
that the unitholder is subject to back-up withholding as a result of failure to
report all interest or dividends; or (c) has been notified by the IRS that such
unitholder is no longer subject to backup withholding.

Certification Instructions - You must cross out item (2) in the paragraph above
if you have been notified by the IRS that you are subject to back-up withholding
because of underreporting interest or dividends on your tax return. However, if
after being notified by the IRS that you were subject to back-up withholding you
received another notification from the IRS that you are no longer subject to
back-up withholding, do not cross out item (2).

Please check this box [ ] if the unitholder has applied for a TIN, a TIN has not
been issued to the unitholder, and either (a) the unitholder has mailed or
delivered an application to receive a TIN to the appropriate IRS Center or
Social Security Administration Office, or (b) the unitholder intends to mail or
deliver an application in the near future (it being understood that if the
unitholder does not provide a TIN to the Purchaser, 30% of all reportable
payments made to the unitholder will be withheld).
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7                            FIRPTA AFFIDAVIT
            (SEE INSTRUCTION 4 - BOX 7 OF THE LETTER OF TRANSMITTAL)
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Section 1445(e)(5) of the Internal Revenue Code and Treas. Reg.1.1445-11T(d)
provide that a transferee of the U.S. real property interest must withhold tax
equal to 10% of the amount realized if the transferor is a foreign person. To
inform the Purchaser that withholding of tax is not required upon this
disposition of a U.S. real property interest, the undersigned hereby certifies
the following under penalties of perjury: (i) the unitholder, if an individual,
is a U.S. citizen or a resident alien for purposes of U.S. income taxation, and
if other than an individual, is not a foreign corporation, foreign partnership,
foreign estate or foreign trust (as those terms are defined in the Internal
Revenue Code and Income Tax Regulations); (ii) the unitholder's U.S. social
security number (for individuals) or employer identification number (for
non-individuals) is correct as furnished in the blank provided for that purpose
on the front of this Acknowledgment and Agreement; and (iii) the unitholder's
home address (for individuals), or office address (for non-individuals), is
correctly printed (or corrected) on the front of this Acknowledgment and
Agreement. The person signing this Acknowledgment and Agreement understands that
this certification may be disclosed to the IRS by the Purchaser and that any
false statements contained herein could be punished by fine, imprisonment, or
both.

[ ] Please check this box if the withholding of tax is required because the
unitholder does not satisfy all of the above conditions.
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                                      -2-



     ACKNOWLEDGMENT AND AGREEMENT. The signatory hereto (the "Signatory") hereby
acknowledges that he or she has received and reviewed (i) the Purchaser's Offer
to Purchase, dated the Offer Date (as supplemented or amended from time to time,
the "Offer to Purchase") relating to the offer by AIMCO Properties, L.P. (the
"Purchaser") to purchase issues in the Partnership, (ii) the Letter of
Transmittal attached as Annex III thereto (the "Letter of Transmittal"), (iii)
this Acknowledgment and Agreement, and (iv) the Instructions hereto in the
Letter of Transmittal, as each may be supplemented or amended from time to time,
and whose terms and conditions are incorporated by reference herein
(collectively, the "Offer"). Capitalized terms used herein but not otherwise
defined herein shall have the meanings ascribed thereto in the Offer to
Purchase. The Signatory hereby understands and agrees that the Letter of
Transmittal is hereby incorporated by reference herein and is hereby made a part
hereof.

     The Signatory hereby makes the representations, warranties, and covenants,
and agrees to the terms and conditions, in each case set forth in the Letter of
Transmittal, and hereby tenders to the Purchaser the units set forth in the box
entitled "Description of Units Tendered" herein, including all interests in any
limited partnership represented by such units (collectively, the "Units"), on
the terms and conditions set forth in the Offer, and certifies under penalties
of perjury that the statements in Box 6 and Box 7 herein are true.

     The Signatory hereby irrevocably constitutes and appoints the Purchaser and
any designees of the Purchaser as the true and lawful agent and attorney-in-fact
of the Signatory with respect to such Units, with full power of substitution
(such power of attorney being deemed to be an irrevocable power coupled with an
interest), to vote or act in such manner as any such attorney and proxy or
substitute shall, in its sole discretion, deem proper with respect to such Units
on any matter submitted for the consent or approval of holders of such Units, to
do all such acts and things necessary or expedient to deliver such Units and
transfer ownership of such Units on the partnership books maintained by the
general partner of the Partnership, together with all accompanying evidence of
transfer and authenticity to, or upon the order of, the Purchaser, to sign any
and all documents necessary to authorize the transfer of the Units to the
Purchaser including, without limitation, the "Transferor's (Seller's)
Application for Transfer" created by the National Association of Securities
Dealers, Inc., if required, and upon receipt by the Information Agent (as the
Signatory 's agent) of the offer price pursuant to the terms of the Offer, to
become a substitute limited partner, to receive any and all distributions made
by the Partnership to which the Purchaser is entitled pursuant to the terms of
the Offer (regardless of the record date for any such distribution), and to
receive all benefits and otherwise exercise all rights of beneficial ownership
of such Units, all in accordance with the terms of the Offer. This appointment
shall be effective upon the purchase of the Units by the Purchaser as provided
in the Offer and shall be irrevocable for a period of the lesser of (i) five
years following the termination of the Offer, or (ii) the maximum period
permitted by applicable law. Upon the purchase of Units pursuant to the Offer,
all prior proxies and consents given by the Signatory with respect to such Units
will be revoked and no subsequent proxies or consents may be given (and if given
will not be deemed effective).

     In addition to and without limiting the generality of the foregoing, the
Signatory hereby irrevocably (i) requests and authorizes (subject to and
effective upon acceptance for payment of any Unit tendered hereby) the
Partnership and its general partners to take any and all actions as may be
required to effect the transfer of the Units to the Purchaser (or its designee)
and to admit the Purchaser as a substitute limited partner in the Partnership
under the terms of the certificate and agreement of partnership of the
Partnership; (ii) empowers the Purchaser and its agent to execute and deliver to
each general partner a change of address form instructing the general partner to
send any and all future distributions to the address specified in the form, and
to endorse any check payable to or upon the order of such unitholder
representing a distribution to which the Purchaser is entitled pursuant to the
terms of the Offer, in each case in the name and on behalf of the tendering
unitholder; (iii) agrees not to exercise any rights pertaining to the Units
without the prior consent of the Purchaser; and (iv) requests and consents to
the transfer of the Units, to be effective on the books and records of the
Partnership as of the effective date set forth in the Offer.

     In addition, the Signatory irrevocably constitutes and appoints the
Purchaser and any designees of the Purchaser as the true and lawful agent and
attorney-in-fact of the Signatory with respect to such Units, with full power of
substitution (such power of attorney being deemed to be an irrevocable power
coupled with an interest), to withdraw any or all of such Units that have been
previously tendered in response to any tender or exchange offer provided that
the price per unit being offered by the Purchaser is equal to or higher than the
price per unit being offered in the other tender or exchange offer. This
appointment is effective immediately and shall continue to be effective unless
and until such Units are withdrawn from the offer by the Signatory prior to the
expiration date (as defined in the Offer to Purchase).

     All authority herein conferred or agreed to be conferred shall survive the
death or incapacity of the Signatory, and any obligations of the Signatory shall
be binding upon the heirs, personal representatives, trustees in bankruptcy,
legal representatives, and successors and assigns of the Signatory.



                                      -3-



                                  INSTRUCTIONS

      (THESE INSTRUCTIONS APPLY IF YOU DESIRE TO PARTICIPATE IN THE OFFER)

For complete instructions on completing this Acknowledgement and Agreement,
please refer to the Letter of Transmittal (Annex III in the Offer to Purchase).

IMPORTANT:

1.   ALL registered owners must sign at the X in Box 1.

2.   When signing as a trustee, executor, administrator, guardian,
     attorney-in-fact, officer of a corporation, or in another fiduciary or
     representative capacity, please indicate your title in Box 1, submit proper
     evidence of your authority to so act, and provide a signature guarantee in
     Box 3.

3.   Please confirm that your name, address and tax identification number are
     correct in Box 2. If there is no label in Box 2, you must fill in this
     information.

4.   Box 4 is to be used only if payment is to be made to someone other than the
     signer.

5.   Box 5 is to be used only if payment is to be mailed to someone other than
     the signer or the signer at a different address from that in Box 2.

6.   Please review Box 6 and Box 7. Crossing out item 2 in Box 6 and/or checking
     the box in Box 7 may result in the withholding of a substantial portion of
     the proceeds payable to you.

7.   Please return all pages of this Acknowledgment and Agreement (along with
     all other required documentation) to the Information Agent at one of its
     addresses below. A postage-paid envelope is enclosed for your convenience.

FOR INFORMATION OR ASSISTANCE IN CONNECTION WITH THE OFFER OR THE COMPLETION OF
THIS ACKNOWLEDGMENT AND AGREEMENT, PLEASE CONTACT THE INFORMATION AGENT AT (800)
461-2657 (TOLL FREE).

                     The Information Agent for the offer is:

                             THE ALTMAN GROUP, INC.

<Table>
                                                                                     

                 By Mail:                               By Overnight Courier:                        By Hand:

         1275 Valley Brook Avenue                   1275 Valley Brook Avenue                 1275 Valley Brook Avenue
       Lyndhurst, New Jersey 07071                 Lyndhurst, New Jersey 07071             Lyndhurst, New Jersey 07071
              (800) 461-2657                             (800) 461-2657                           (800) 461-2657

                             By Facsimile:                                 By Telephone:

                            (201) 460-0050                            TOLL FREE (800) 461-2657


</Table>

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