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                                                                 Exhibit 99.6

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THIS FORM IS TO BE COMPLETED ONLY BY GROVE LP LIMITED PARTNERS WHO ARE
SUBJECT TO A DEFICIT RESTORATION OBLIGATION UNDER SECTION 13.5 OF THE
AGREEMENT OF LIMITED PARTNERSHIP OF GROVE LP AND WHO ELECT TO RECEIVE UNITS
OF ERP LIMITED PARTNERSHIP INTEREST IN EXCHANGE FOR THEIR UNITS OF GROVE LP
LIMITED PARTNERSHIP INTEREST PURSUANT TO THE TRANSACTION DESCRIBED HEREIN.

IF YOU DO NOT MAKE A DEFICIT RESTORATION OBLIGATION ELECTION OR DO NOT
PROPERLY SUBMIT THE DEFICIT RESTORATION OBLIGATION ELECTION FORM BY THE
ELECTION DEADLINE, YOU WILL BE DEEMED TO HAVE ELECTED NOT TO BE SUBJECT TO A
DEFICIT RESTORATION OBLIGATION.

YOU SHOULD REVIEW AND CAREFULLY CONSIDER THE CONSEQUENCES OF ELECTING OR NOT
ELECTING TO BECOME SUBJECT TO A DEFICIT RESTORATION OBLIGATION AS SET FORTH
IN THE PROXY STATEMENT/PROSPECTUS DATED OCTOBER 2, 2000 BEFORE MAKING AN
ELECTION.
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             DEFICIT RESTORATION OBLIGATION ELECTION FORM

     This Deficit Restoration Obligation Election Form is being sent in
connection with the proposed merger of a subsidiary of ERP Operating Limited
Partnership ("ERP") and Grove Operating, L.P. ("Grove LP") pursuant to the
Agreement and Plan of Merger dated as of July 17, 2000 among Grove Property
Trust ("Grove"), Grove LP and ERP (the "Partnership Merger"), to the limited
partners of Grove LP who (i) are subject to a deficit restoration obligation
under the Agreement of Limited Partnership of Grove LP (the "Grove LP
Partnership Agreement") and (ii) elect to receive units of ERP limited
partnership interest in exchange for their units of Grove LP limited
partnership interest (the "Holder").

    THE ELECTION DEADLINE IS 5:00 P.M. (BOSTON TIME) ON OCTOBER 30, 2000.

      BY MAIL                     BY HAND                BY OVERNIGHT CARRIER
     EquiServe         Securities Transfer & Reporting         EquiServe
 Corporate Actions               Services               Attn: Corporate Actions
    PO Box 8029                C/O EquiServe               150 Royall Street
Boston, MA 02266-8029   100 Williams Street, Galleria      Canton, MA 02021
                              New York, NY 10038


        IF YOU REQUIRE ADDITIONAL INFORMATION, PLEASE CALL EQUISERVE
                    (THE "PAYING AGENT") AT 800-733-5001.

     If this Deficit Restoration Obligation Election Form is properly
submitted before the Election Deadline, the Holder, if such Holder so elects,
will become subject to a deficit restoration obligation under ERP's Fifth
Amended and Restated Agreement of Limited Partnership ("ERP Partnership
Agreement") for an amount not to exceed such Holder's current amount of
deficit restoration obligation under the Grove LP Partnership Agreement.

   PLEASE READ THE INSTRUCTIONS IN THIS DEFICIT RESTORATION OBLIGATION
ELECTION FORM CAREFULLY BEFORE COMPLETING THE DEFICIT RESTORATION
                        OBLIGATION ELECTION BELOW.

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                 DEFICIT RESTORATION OBLIGATION ELECTION

CHOOSE ONE:
                                         RESTORATION
   [    ]  HOLDER ELECTS TO BE
           SUBJECT TO DEFICIT            AMOUNT: __________________________*
           RESTORATION OBLIGATION

   [    ]  HOLDER ELECTS NOT TO BE       * May not exceed current maximum
           SUBJECT TO DEFICIT              under Grove LP Partnership Agreement
           RESTORATION OBLIGATION
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NAME AND ADDRESS OF HOLDER OF UNITS OF GROVE LP LIMITED PARTNERSHIP INTEREST:



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                               ELECTION INSTRUCTIONS

     The appropriate box must be checked above in order to make a deficit
restoration obligation election (a "DRO Election").  If you do not make a DRO
Election or do not properly submit the Deficit Restoration Obligation
Election Form by the Election Deadline, you will be deemed to have elected
NOT to be subject to a deficit restoration obligation under the ERP
Partnership Agreement.  If you elect to become subject to a deficit
restoration obligation under the ERP Partnership Agreement you must enter a
"Restoration Amount". The Restoration Amount is the maximum deficit balance
amount that you would be required to contribute to ERP in the case of a
liquidation or dissolution of ERP; provided, however, such Restoration Amount
may not exceed your current "Protected Amount", as defined in the Grove LP
Partnership Agreement.

     All Holders wishing to make a DRO Election must deliver to the Paying
Agent, as agent for ERP, a properly completed original Deficit Restoration
Obligation Election Form prior to the Election Deadline, which is 5:00 p.m.
(Boston Time) on October 30, 2000.

     All Holders submitting a Deficit Restoration Obligation Election Form
that is received by the Paying Agent after the Election Deadline will be
deemed NOT to be subject to a deficit restoration obligation under the ERP
Partnership Agreement.

     You will not be subject to a deficit restoration obligation if :

     -  No DRO Election choice is indicated;

     -  More than one DRO Election choice is indicated;

     -  You fail to follow the instructions on this Deficit Restoration
        Obligation Election Form or otherwise fail to properly make a DRO
        Election; or

     -  A completed original Deficit Restoration Obligation Election Form is
        not received by the Paying Agent prior to the Election Deadline.

     Notwithstanding anything to the contrary in this Deficit Restoration
Obligation Election Form, ERP reserves the right, which it may delegate in
whole or in part to the Paying Agent, to waive any errors in a completed
Deficit Restoration Obligation Election Form.  However, ERP shall be under no
obligation to do so.

     This Deficit Restoration Obligation Election Form may be revoked by (i)
advising the Paying Agent in writing at the appropriate address indicated
above before the Election Deadline or (ii) delivering to the Paying Agent
prior to the Election Deadline a properly completed Deficit Restoration
Obligation Election Form dated after the date of your then prior Deficit
Restoration Obligation Election Form.

     This Deficit Restoration Obligation Election Form must be (i) completed
and signed in ink (blue ink preferred) in the space provided below and (ii)
mailed or delivered to the Paying Agent at the appropriate address set forth
above. In order to make a proper DRO Election, these actions must be taken in
a timely fashion such that the Deficit Restoration Obligation Election Form
is received by the Paying Agent at/or prior to the Election Deadline.

     THE METHOD OF DELIVERY OF THE DEFICIT RESTORATION OBLIGATION ELECTION
FORM IS AT THE ELECTION AND RISK OF THE HOLDER. DELIVERY OF THIS DEFICIT
RESTORATION OBLIGATION ELECTION FORM TO AN ADDRESS OTHER THAN AS SET FORTH
WILL NOT CONSTITUTE A VALID DELIVERY TO THE PAYING AGENT.

     CONSUMMATION OF THE PARTNERSHIP MERGER IS SUBJECT TO THE SATISFACTION OF
VARIOUS CLOSING CONDITIONS.  NO OBLIGATIONS RELATING TO A DEFICIT RESTORATION
OBLIGATION ELECTION WILL BECOME EFFECTIVE PRIOR TO THE EFFECTIVE TIME OF THE
PARTNERSHIP MERGER.

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The undersigned represents and warrants to ERP and the Paying Agent that the
undersigned is subject to a deficit restoration obligation under the Grove LP
Partnership Agreement, has elected to receive units of ERP limited
partnership interest in exchange for units of Grove LP limited partnership
interest, pursuant to the Partnership Merger has thoroughly read the proxy
statement/prospectus dated October 2, 2000 and fully understands the
consequences of electing or not electing to become subject to a deficit
restoration obligation under the ERP Partnership Agreement.

                            PLEASE SIGN HERE

Signature: ____________________________________________________________________

Dated: ________________________________________________________________________

Name: _________________________________________________________________________
                                 (please print)
Capacity: _____________________________________________________________________

Daytime Area Code and Telephone Number: _______________________________________

If signed by a trustee, executor, administrator, guardian, attorney-in-fact,
officer of a corporation or other person acting in a fiduciary or
representative capacity, the capacity of the person signing should be
indicated.
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