AIMCO
                             AIMCO PROPERTIES, L.P.
                           c/o The Altman Group, Inc.
                            1275 Valley Brook Avenue
                           Lyndhurst, New Jersey 07071
                                 (800) 461-2657

                                   May 9, 2003

                                OFFER TO PURCHASE
                          LIMITED PARTNERSHIP UNITS OF
                 WINTHROP GROWTH INVESTORS 1 LIMITED PARTNERSHIP
                          FOR $560.00 PER UNIT IN CASH

Dear Limited Partner:

         We have begun a tender offer to purchase limited partnership units of
your partnership for $560.00 per unit. Our offer is being made pursuant to the
enclosed Offer to Purchase, which sets forth all of the terms and conditions of
the offer. Please carefully review the Offer to Purchase prior to making a
decision whether or not to tender your interests. The offer is scheduled to
expire at midnight, New York City time, on June 6, 2003, unless otherwise
extended. You will not be required to pay any partnership transfer fees in
connection with any sale of your units pursuant to our offer.

         If we purchase your tendered units, you will receive cash, but you may
recognize a gain or loss for federal income tax purposes. If you retain your
units, you will continue to be a limited partner. However, you may not be able
to liquidate your investment until the partnership terminates.

         As with any investment decision, there are benefits and detriments to
you from accepting or declining our offer. The managing general partners of your
partnership, Two Winthrop Properties, Inc., a Massachusetts corporation, is
remaining neutral and makes no recommendation as to whether you should tender or
refrain from tendering your units in any offer. The general partner believes
that you must make your own decision whether or not to participate in any offer,
based upon a number of factors described in the Offer to Purchase.

         The managing general partner of your partnership is our affiliate. As a
result, it has substantial conflicts of interest with respect to our offer. This
conflict may affect the general partners' ability to reconcile our interests
with those of the other limited partners, particularly in assessing the fairness
of our offer price. We seek to purchase units at a low price, but you desire to
sell units at a high price. In addition, affiliates of your general partner are
entitled to receive fees for managing the partnership and for certain
transactions involving the partnership.

         If you desire to tender any of your units in response to our offer, you
should complete and sign the enclosed acknowledgment and agreement in accordance
with the instructions set forth in




the letter of transmittal attached as Annex II to the Offer to Purchase. The
signed acknowledgment and agreement and any other required documents should be
sent to our Information Agent, The Altman Group, Inc., prior to the expiration
of our offer. The address of the Information Agent for all forms of delivery is
1275 Valley Brook Avenue, Lyndhurst, New Jersey 07071.

         If you have any questions or require further information, please call
the Information Agent, toll free, at (800) 461-2657.

                                                     Very truly yours,



                                                     AIMCO PROPERTIES, L.P.