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                                                                   EXHIBIT 4(a)


                                      AIMCO
                             AIMCO PROPERTIES, L.P.
                    c/o River Oaks Partnership Services, Inc.
                  P.O. Box 2065 S. Hackensack, N.J., 07606-2065
                                 (888) 349-2005

                                October 18, 2001

                                OFFER TO PURCHASE
                          LIMITED PARTNERSHIP UNITS OF
                      VMS NATIONAL RESIDENTIAL PORTFOLIO I
                           FOR $1,082 PER UNIT IN CASH


Dear Limited Partner:

         We have begun a tender offer to purchase limited partnership units of
your partnership for $1,082 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 November 14, 2001, 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 general partner of your
partnership is remaining neutral and makes no recommendation as to whether you
should tender or refrain from tendering your units in any offer. Although the
general partner believes our offer is fair, it also 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 general partner of your partnership is our subsidiary. As a result,
it has substantial conflicts of interest with respect to our offer. This
conflict may affect the general partner's 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, your general partner is entitled to
receive fees for certain transactions involving the partnership and its
property, and the partnership's property manager, which is also our subsidiary,
is entitled to receive fees for managing the partnership's property.

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         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 the Information Agent, River Oaks
Partnership Services, Inc., prior to the expiration of our offer. The addresses
for the Information Agent are P.O. Box 2065, South Hackensack, New Jersey
07606-2065 or by overnight courier service or by hand at 111 Commerce Road,
Carlstadt, New Jersey 07072 -- Attention: Reorganization Department.

         If you have any questions or require further information, please call
the Information Agent, toll free, at (888) 349-2005.


                                                     Very truly yours,



                                                     AIMCO PROPERTIES, L.P.