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                                                                EXHIBIT 10.52

                                   PUT-CALL OPTION
                                     AGREEMENT


            THIS  PUT-CALL OPTION AGREEMENT (this "Agreement") is dated and made
effective as of January 6, 1997, by and between NHP Incorporated, a Delaware
corporation ("NHP"), and Property Resources Corporation, a New York corporation
("PRC").

                                      RECITALS

A.    NHP and PRC own of record and beneficially 15% and 85%, respectively,
      of the membership interests in NHP/PRC Management Company LLC, a
      Delaware limited liability company (the "LLC").

B.    NHP and PRC desire to enter into an agreement, whereby (1) NHP shall
      have the option to purchase all of PRC's membership interests in the
      LLC (the "Membership Interests") (the "Call Option") and (2) PRC shall
      have the option to cause NHP to purchase all of the Membership
      Interests (the "Put Option"), subject to the terms and conditions set
      forth herein.

      NOW, THEREFORE, in consideration of the premises and the mutual agreements
contained herein, the parties hereto agree as follows:

      1.     GRANTS OF CALL OPTION AND PUT OPTION.  Subject to the terms and
             conditions set forth herein, PRC hereby grants the Call Option to
             NHP, and NHP hereby grants the Put Option to PRC.

      2.     EXERCISE OF OPTIONS.

             (a)   CALL OPTION.  NHP may exercise the Call Option, in whole but
                   not in part, by notifying PRC, in accordance with Section
                   2(c) hereof, of its intention to do so (the "Call Exercise
                   Notice") at any time during the period from and including
                   the one (1) year anniversary of the "Put Option Expiration
                   Date" (hereinafter defined) to and including the date which
                   is 120 days after receipt of notice from PRC regarding the
                   occurrence of the Put Option Expiration Date.

             (b)   PUT OPTION.  PRC may exercise the Put Option, in whole but
                   not in part, by notifying NHP, in accordance with Section
                   2(c) hereof, of its intention to do so (the "Put Exercise
                   Notice") at any time during the period from and including
                   the date hereof to and including January 15, 2002 (the "Put
                   Option Expiration Date").  The Put Option may be exercised
                   notwithstanding the occurrence of an Event of Default (as
                   defined below).

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             (c)   NOTICE.  The Call Exercise Notice or the Put Exercise
                   Notice, as the case may be, shall be in writing and shall
                   specify a place, time and date, not earlier than 30 days nor
                   later than 60 days from the date of such notice, for the
                   closing of the purchase of the Membership Interests;
                   provided, however, that in the case of when the Put Option
                   is exercised, and upon the occurrence of an Event of Default
                   (as such term is defined in the Assignment dated as of the
                   date hereof by PRC in favor of NHP (the "Assignment")), the
                   closing shall be accelerated to a date no later than the
                   date on which NHP seeks payment of the Obligations (as such
                   term is defined in the Assignment).

      3.     PURCHASE PRICE PAYMENT.

             (a)   CALL OPTION.  The purchase price for the purchase of the
                   Membership Interests upon the exercise of the Call Option
                   shall be Four Million Three Hundred Fifty-three Thousand
                   Nine Hundred Dollars ($4,353,900.00).

             (b)   PUT OPTION.  The purchase price for the purchase of the
                   Membership Interests upon the exercise of the Put Option
                   shall be Three Million Seven Hundred Eighty-six Thousand
                   Dollars ($3,786,000.00).

             (c)   PAYMENT.  The purchase price payable pursuant to Section
                   3(a) or 3(b) (the "Purchase Price") shall be paid in cash at
                   the closing on the purchase of the Membership Interests.
                   The Purchase Price shall be paid in immediately available
                   funds by wire transfer to a bank account designated by PRC,
                   or by such other arrangement as may be mutually agreed upon
                   in writing by NHP and PRC.

      4.     REPRESENTATIONS AND  WARRANTIES.  Each party hereto hereby
             represents and  warrants to the other party hereto as follows:

             (a)   AUTHORIZATION.  Such party has all requisite corporate
                   power and authority to enter into this Agreement and to
                   consummate the transactions contemplated hereby.  This
                   Agreement is a legal, valid and binding obligation of such
                   party enforceable against it in accordance with its terms.

             (b)   AGREEMENT NOT IN BREACH OF OTHER INSTRUMENTS.  The
                   execution, delivery and performance of this Agreement, and
                   the consummation of the transactions contemplated hereby,
                   will not violate, or result in a breach of any of the terms
                   or provisions of, or constitute a default under, or conflict
                   with, such party's organizational documents, or any
                   agreement, indenture or other instrument to which such party
                   is a party or by which it or any of its properties is bound,
                   or any judgment, decree, order, writ, award or injunction of
                   any court,

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                   governmental body or arbitrator, or any law, rule
                   or regulation applicable to such party.

             (c)   CONSENTS AND APPROVALS.  No consent, approval or
                   authorization from any governmental entity or otherwise,
                   notice to or filing with is required in connection with the
                   execution, delivery and performance of this Agreement by
                   such party and/or the consummation by such party of the
                   transactions contemplated hereby, except for notice required
                   by the LLC Operating Agreement of even date herewith.

      5.     EXPENSES.  Except as may be expressly set forth herein, each of
             the parties hereto shall bear and pay all costs and expenses
             incurred by it or on its behalf in connection with the
             transactions contemplated hereunder, including fees and expenses
             of its own financial consultants, investment bankers, accountants
             and counsel.  In the event the Put Option is exercised by PRC, and
             NHP fails to pay PRC the purchase price set forth in Section 3(b)
             hereof, in accordance with the terms and conditions hereof, NHP
             promises to pay all costs of collection, including, but not
             limited to, reasonable attorneys' fees and expenses, whether suit
             be brought or not.  In the event that the Call Option is exercised
             by NHP, and PRC fails to immediately deliver the Membership
             Interests to NHP in accordance with the terms and conditions
             hereof, PRC promises to pay all costs of collection, including,
             but not limited to, reasonable attorneys' fees and expenses,
             whether or not suit is filed.

      6.     HEADINGS.  The headings in this Agreement are for convenience of
             reference only and shall not limit or otherwise affect the meaning
             of this Agreement.

      7.     SEVERABILITY.  If any one or more of the provisions herein, or the
             application thereof in any circumstances, is held invalid, illegal
             or unenforceable in any respect for any reason, the validity,
             legality and enforceability of any such provision in every other
             respect, and of the remaining provisions, shall not be in any way
             impaired or affected.  In such event, there shall be added as part
             of this Agreement a provision as similar in terms to such illegal,
             invalid or unenforceable provision as may be possible and be
             legal, valid and enforceable.  The effective date of the added
             provision shall be the date upon which the prior provision was
             held to be invalid, illegal or unenforceable.

      8.     ENTIRE AGREEMENT; BINDING EFFECT.  This Agreement constitutes the
             entire agreement by and between the parties with respect to the
             subject matter hereof, and there are no representations,
             warranties, covenants, or obligations with respect thereto except
             as set forth herein.  This Agreement supersedes all prior and
             contemporaneous agreements, understandings, negotiations and
             discussions, written or oral, of the parties hereto, relating to
             any transaction contemplated hereunder.  Nothing in this Agreement
             is intended or shall be construed to confer upon or to give any
             person

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             other than the parties hereto and their respective legal
             representatives, successors and permitted assigns any rights or
             remedies under or by reason of this Agreement.

      9.     NOTICES.  All notices, directions, requests, consents and other
             communications hereunder ("Communications") shall be in writing
             and shall be deemed given (i) when delivered personally to the
             recipient, (ii) when sent to the recipient by telecopy (with
             receipt electronically confirmed by sender's machine) if prior to
             6 p.m. (Eastern Time) on a business day, otherwise on the next
             business day, or (iii) one (1) business day after the date sent to
             the recipient by reputable express courier service (charges
             prepaid) to the parties at the following  addresses or telecopier
             numbers (or at such other address, or telecopy number for a party
             as shall be specified by like notice):  (a) if to NHP at 8065
             Leesburg Pike, Suite 400, Vienna, VA 22182, Attention: Mr. Robert
             M. Greenfield, Executive Vice President and a copy to Joel Bonder,
             Esquire, General Counsel (Fax: 202-371-2103), with a copy to
             Kenneth G. Lore, Esquire, Swidler & Berlin, 3000 K Street, N.W.,
             Washington, D.C.  20007 (Fax: 202-424-7643); (b) if to PRC at 19
             East 82nd Street, New York, NY 10028, Attention: Mr. Frank Linde
             (Fax: 212-737-3989) with a copy to Jack H. Nusbaum, Esquire,
             Willkie Farr & Gallagher, One Citicorp Center, 153 East 53rd
             Street, New York, NY 10022 (Fax: 212-821-8111).  All
             Communications shall be deemed to have been received:  (i) when
             received, if personally delivered; (ii)  when receipt confirmed,
             if telecopied; and (iii) the next business day after timely
             delivery to the courier, if sent by overnight courier.  Any person
             entitled to receive notice under this Section 9 may change such
             person's address or other information by notice given in
             accordance with this Section 9.

     10.     FURTHER ASSURANCES.  Each party hereto agrees to do such further
             things and to execute such further documents as may be necessary
             to effectuate this Agreement and the transactions contemplated
             herein, including, but not limited to, securing all necessary
             consents and permissions, and giving all necessary notices.

     11.     SUCCESSORS AND ASSIGNS.  This Agreement shall be binding upon, and
             shall inure to the benefit of, the parties hereto and their
             respective successors and permitted assigns.   Neither this
             Agreement nor any of the rights, interests or obligations
             hereunder may be transferred or assigned by any party hereto
             without the express prior written consent of the other party
             hereto; provided, however, that (i) NHP may  transfer and assign
             this Agreement to any "affiliate" (as such term is defined in Rule
             405 of Regulation C promulgated under the Securities Act of 1933,
             in effect as of the date hereof) of NHP without the prior written
             consent of PRC, which assignment shall not relieve NHP of its
             obligations hereunder, and (ii) PRC's (and any subsequent
             assignee's) rights and obligations hereunder shall automatically
             be assigned and transferred, with no further action required by
             any party, in connection with the assignment and transfer of the
             Membership Interests effected in accordance with the Operating
             Agreement of NHP/PRC Management Company LLC dated the

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             date hereof by and between PRC and NHP Management Inc., which
             assignment and transfer will not relieve PRC of any liability
             hereunder.

     12.     COUNTERPARTS.  This Agreement may be executed in any number of
             counterparts, and each such counterpart shall be deemed to be an
             original instrument, but all such counterparts together shall
             constitute but one agreement.

     13.     SPECIFIC PERFORMANCE.  The parties agree that damages would be an
             inadequate remedy for a breach of the provisions of this Agreement
             by either party hereto and that this Agreement may be enforced by
             either party hereto through injunctive or other equitable relief,
             in addition to, but not in limitation of, any and all other
             remedies available to the parties.  In the event that either party
             shall institute any action specifically to enforce the other
             party's performance of this Agreement, such other party shall
             waive the defense that the party seeking specific performance has
             an adequate remedy at law.

     14.     GOVERNING LAW.  This Agreement shall be governed by and construed
             in accordance with the laws of the State of New York applicable to
             contracts entered into and performed fully in such state (without
             giving effect to conflict of law principles.)

     15.     ARBITRATION.  Except to the extent this Agreement provides
             otherwise, any dispute arising under this Agreement shall be
             resolved by arbitration as hereinafter provided.  The party
             desiring arbitration shall give written notice to that effect to
             the other party and to such party's counsel, as provided for in
             Section 9 hereof.  The party initiating the arbitration shall send
             a copy of the notice initiating the arbitration to the American
             Arbitration Association (or its successor) and shall request that
             the American Arbitration Association select within 10 days
             thereafter an individual who meets the following criteria to act
             as the arbitrator.  The arbitrator must be (i) "independent,"
             i.e., not having at that time or at any time within the
             immediately preceding five (5) years a substantial relationship
             with either party to the arbitration, any Affiliate of either such
             party, or any officer or director of any such party or Affiliate
             (ii) an attorney having at least ten (10) years experience, and
             (iii) knowledgeable in the area of finance.  No party to the
             arbitration shall have any right to object to the individual named
             as the arbitrator except upon the ground that the named individual
             does not meet the aforesaid criteria.  If more than one
             arbitration is conducted pursuant to this Agreement, the parties
             agree to use the same arbitrator, subject to his or her
             availability.  The arbitration shall be conducted in the City of
             New York and, to the extent consistent with this Paragraph, in
             accordance with the expedited procedures set forth in and
             otherwise in accordance with the then Commercial Arbitration Rules
             of the American Arbitration Association (or any organization
             successor thereto).  The arbitrator shall be instructed to proceed
             with all reasonable diligence to resolve the dispute by no later
             than 30 days after the date on which the American Arbitration

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             Association received the request to initiate the arbitration, to
             render his decision in writing and to deliver counterpart copies
             thereof to each of the parties.  The arbitrator may issue a
             default award against a party that fails to appear at any meeting
             or hearing scheduled by the arbitrator or which attempts to delay
             the arbitration.  Such decision shall be binding, final and
             conclusive on the parties.  Judgment may be had on the decision so
             rendered in any court of competent jurisdiction, federal or state,
             and may be enforced in accordance with the laws of the State of
             New York.  The fees of the arbitrator, the fees and expenses of
             respective counsel engaged by the parties, the fees and expenses
             of expert witnesses and other witnesses called by the parties and
             the cost of transcripts shall be paid by the party against which
             the dispute is resolved, unless otherwise specified by the
             arbitrator.

     16.     NO IMPLIED WAIVERS; REMEDIES.  No failure or delay on the part of
             either party in exercising any right, privilege, power or remedy
             under this Agreement, and no course of dealing between parties
             hereto, shall operate as a waiver of any such right, privilege,
             power or remedy; nor shall any single or partial exercise of any
             right, privilege, power or remedy under this Agreement preclude
             any other or further exercise of such right, privilege, power or
             remedy or the exercise of any other right, privilege, power or
             remedy.  No waiver shall be asserted against any party unless
             signed in writing by such party.  The rights, privileges, powers
             and remedies available to the parties are cumulative and not
             exclusive of any other rights, privileges, powers or remedies
             provided by statute, at law, in equity, or otherwise.  Except as
             provided in this Agreement, no notice to or demand on either party
             in any case shall constitute a waiver of the right of the party
             giving such notice or making such demand to take any other or
             further action in any circumstances without notice or demand.

     17.     CONSTRUCTION.  No failure or delay on the part of either party in
             exercising any right, privilege, power or remedy under this
             Agreement, and no course of dealing between parties hereto, shall
             operate as a waiver of any such right, privilege, power or remedy;
             nor shall any single or partial exercise of any right, privilege,
             power or remedy under this Agreement preclude any other or further
             exercise of such right, privilege, power or remedy or the exercise
             of any other right, privilege, power or remedy.  No waiver shall
             be asserted against any party unless signed in writing by such
             party.  The rights, privileges, powers and remedies available to
             the parties are cumulative and not exclusive of any other rights,
             privileges, powers or remedies provided by statute, at law, in
             equity, or otherwise.  Except as provided in this Agreement, no
             notice to or demand on either party in any case shall constitute a
             waiver of the right of the party giving such notice or making such
             demand to take any other or further action in any circumstances
             without notice or demand.

                             [Signatures begin on next page]

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      IN WITNESS WHEREOF, each of the parties hereto has executed this Agreement
as of the date first written above.

<TABLE>
<CAPTION>
                                          NHP INCORPORATED

                                          <S> <C>
                                          BY:
                                              -------------------------------
                                              NAME:  Robert M. Greenfield
                                              TITLE:  Executive Vice President
</TABLE>

<TABLE>
<CAPTION>
                                          PROPERTY RESOURCES CORPORATION

                                          <S> <C>
                                          BY:
                                              -------------------------------
                                              NAME:  John Chatzky
                                              TITLE:  Vice President
</TABLE>

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