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                                                                   Exhibit 10.70

                                                          JHREF Loan No. 3212525


                         TENANT IMPROVEMENT AND LEASING
                              COMMISSIONS AGREEMENT



     THIS TENANT IMPROVEMENT AND LEASING COMMISSIONS AGREEMENT (the "AGREEMENT")
is made as of the 1st day of March, 1999 by and between BIRCH POND REALTY
CORPORATION, a Delaware corporation (doing business in the State of New
Hampshire as BPRC) ("BORROWER") and JOHN HANCOCK REAL ESTATE FINANCE, INC., a
Delaware corporation ("LENDER").

                              W I T N E S S E T H:

     WHEREAS, Borrower is the owner of a certain property (the "MORTGAGED
PROPERTY") located in Tilton, Belknap County, New Hampshire, more particularly
described in the Loan Documents (as hereinafter defined), and in connection
therewith, Lender has loaned Borrower the principal sum of TWELVE MILLION AND
00/100 DOLLARS ($12,000,000.00) (the "LOAN"); and

     WHEREAS, the Loan is evidenced by a Note executed by Borrower as of even
date herewith in the principal amount of $12,000,000.00 payable to the order of
Lender (the "NOTE"); and

     WHEREAS, the Note is secured by a Mortgage dated as of even date herewith,
which encumbers the Mortgaged Property, and by the other "LOAN DOCUMENTS" (as
such term is defined in the Note); and

     WHEREAS, Lender requires, as a condition of the Loan, that Borrower deposit
with Lender certain funds, to be held, released and used as provided in this
Agreement to reimburse the cost of completing the Tenant Improvements and paying
for Leasing Commissions as hereinafter described.

     NOW, THEREFORE, in consideration of the foregoing, the covenants and
conditions contained in this Agreement and other good and valuable
consideration, the receipt and legal sufficiency of which are hereby
acknowledged, Borrower and Lender hereby agree as follows:

     1. DEFINITIONS. Any capitalized term utilized herein shall have the meaning
as specified in the Mortgage, unless such term is otherwise specifically defined
herein. For purposes of this Agreement, the following capitalized terms shall
have the meanings indicated:

          (a) TENANT IMPROVEMENTS shall mean construction or modification of
     improvements on or installation of fixtures or equipment in the Mortgaged
     Property as required to be performed by Borrower pursuant to the terms of a
     Lease (as hereinafter defined) necessary for the space, or a portion
     thereof ("TENANT PREMISES") subject to such Lease to be deemed ready for
     occupancy and/or use by a tenant.

          (b) LEASING AGENT shall mean a licensed real estate broker in the
     state where the Mortgaged Property is located who is not affiliated with
     the Borrower or its principals.


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                                                          JHREF Loan No. 3212525


          (c) LEASING COMMISSIONS shall mean reasonable and customary
     commissions paid to a Leasing Agent pursuant to a written agreement with
     such Leasing Agent under which such Leasing Agent has procured a tenant for
     a Tenant Premises in connection with an Lease.

          (d) LEASE shall mean a lease for space in the Mortgaged Property
     (approved by the Lender if such right of approval is required by the Loan
     Documents). For the purposes of this Agreement, the Lease shall be as set
     forth on EXHIBIT A attached hereto.

     2. THE DEPOSIT(S).

          (a) INITIAL DEPOSIT. Concurrently with its execution of this
     Agreement, Borrower has deposited with Lender the cash sum of Zero Dollars
     ($0.00) ("INITIAL DEPOSIT").

          (b) MONTHLY DEPOSITS. In addition, on each date that a regularly
     scheduled payment of principal and/or interest is due under the Note,
     Borrower shall deposit with Lender the applicable monthly deposit ("MONTHLY
     DEPOSIT") required as set forth in SCHEDULE 1, attached hereto. The Initial
     Deposit, if any, and the Monthly Deposits, if any, and all other funds
     deposited by Borrower pursuant to this Agreement shall hereinafter be
     collectively referred to as the "Reserve".

     The Reserve shall be held and released by Lender, in accordance with the
terms and conditions of this Agreement. Lender (or a designated representative
of Lender) shall have the sole right to make withdrawal of the Reserve, in
accordance with the terms and conditions of this Agreement.

     3. THE RESERVE.

          (a) Lender shall hold the Reserve in one or more interest bearing
     accounts ("ACCOUNTS" or "ACCOUNT") invested at such financial institutions
     as Lender shall select in its sole discretion, more particularly described
     in 3(b) below.

          (b) Any interest earned on the Account shall be for the benefit of
     Borrower and shall be added to the principal balance of the Account and
     disbursed in accordance with this Agreement. Lender shall not be
     responsible for any losses resulting from investment of monies in the
     Reserve or for obtaining any specific level or percentage of earnings on
     such investment.

     The Reserve deposited pursuant to Section 3(b) shall be invested by the
     Lender in Accounts maintained in the name of the Lender as secured party
     with respect to the Borrower in commercial or savings banks provided that
     such Accounts shall at all times be with an institution insured by the
     Federal Deposit Insurance Corporation to the fullest possible extent
     consistent with applicable laws (currently $100,000), and further provided
     that the Accounts shall be demand accounts, withdrawable at the time for
     payment for Tenant Improvements or Leasing Commissions, and the funds so
     obtained shall be disbursed pursuant to the terms of this Agreement.

     The Account options are:


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                                                          JHREF Loan No. 3212525

              X    Cash Investment Account at Wachovia Bank of North Carolina,
           ------  Charlotte, North Carolina

                   Business Premier Money Market Account at Wachovia Bank of 
           ------  North Carolina, Charlotte, North Carolina (minimum balance of
                    $10,000)

Account selection at the execution of this Agreement is for the life of the
Loan.

The above selected bank and any assign or successor to such bank shall
hereinafter be referred to as "BANK." Borrower acknowledges that the Bank is
hereby selected by Lender with Borrower's consent, and Borrower agrees that any
loss of funds while in the hands of Bank is at the risk of the Borrower.
Borrower further acknowledges and agrees to be fully responsible for any and all
fees charged by the Bank for the Account that is maintained therein. Lender
reserves the right in its sole discretion to move the Account to another bank in
the event the Bank fails to satisfy Lender or rating agency criteria, at which
time, Borrower may be required to choose from alternative account options.

     4. USE OF THE RESERVE. The Reserve shall be held as additional security to
secure Borrower's repayment of the Note and performance of all other covenants
and conditions required on the part of Borrower to be observed or performed
hereunder and under the Loan Documents.

     5. TERM; TERMINATION. The Reserve shall remain on deposit with Lender in
accordance with the terms of this Agreement for so long as any sums remain due
and payable to Lender under the Loan Documents. Upon the full and final payment
to Lender of all such sums, Lender shall return to Borrower the portion of the
Reserve then being held by Lender (including any accrued interest thereon).

     6. REMEDIES.

          (a) In order to secure Borrower's repayment of the Note and
     performance of all other covenants and conditions required on the part of
     Borrower to be observed or performed hereunder and under the Loan
     Documents, Borrower, to the extent Borrower possesses any interest in the
     Reserve and the Account, hereby pledges, assigns and grants to Lender a
     continuing first lien security interest in the Reserve and the Account, and
     Lender is hereby given a lien upon, security title to, and a security
     interest in the Reserve and the Account and all documents evidencing the
     Reserve and the Account. Borrower hereby acknowledges that Lender has
     complete dominion and control over the Reserve and the Account, and
     Borrower shall not, without the express written consent of Lender, have any
     access to or right to draw against any of the Reserve or the Account.

          (b) Upon the occurrence of an Event of Default or in the event and
     during the continuation of Borrower's breach of any provision of this
     Agreement, Lender may terminate this Agreement and shall have all remedies
     available under Article 9 of the Uniform Commercial Code, under common law,
     and under any other applicable laws and, in addition, may retain the
     Reserve then being held pursuant to this Agreement and apply such Reserve
     in such order and in such amounts as Lender shall elect, in its sole and
     absolute discretion: (i) to repayment of the indebtedness evidenced by the
     Note and the Loan Documents; (ii) toward reimbursement of Lender for any
     losses or expenses (including, without limitation, legal fees) suffered or
     incurred by Lender 


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                                                          JHREF Loan No. 3212525

     as a result of such default; and/or (iii) in order to proceed under
     existing contracts or enter into contracts with third parties to make or
     complete the Tenant Improvements.

          In the Event of Default, Lender shall have the right, but not the
     obligation, to enter onto the Mortgaged Property and perform any and all
     work and labor necessary to make or complete the Tenant Improvements and/or
     employ watchmen to protect the Mortgaged Property from damage. All sums so
     expended by Lender shall be construed to have been paid to Borrower and
     shall be secured by the Mortgage. Borrower hereby constitutes and appoints
     Lender its true and lawful attorney-in-fact with full power of substitution
     to complete or undertake the Tenant Improvements in the name of the
     Borrower, enter into contracts for the completion of the Tenant
     Improvements, incur such obligations, enforce any contracts or agreements
     made by or on behalf of Borrower (including the prosecution and defense of
     all actions or proceedings in connection with the Tenant Improvements and
     the payment, settlement, or compromise of all claims for materials and work
     performed in connection with the Tenant Improvements) and do any and all
     things necessary or proper to complete the Tenant Improvements. This power
     of attorney shall be construed to be a power coupled with an interest which
     cannot be revoked. Borrower hereby assigns to Lender all rights, claims and
     causes of action Borrower may have against any person or entities supplying
     labor or materials in connection with the Tenant Improvements; provided,
     however, that Lender may not pursue any such right, claim or cause of
     action unless an Event of Default shall have occurred under the Loan
     Documents or Borrower shall have otherwise breached any provision in this
     Agreement.

     7. INDEMNIFICATION. Borrower shall hold harmless, indemnify and defend
Lender from and against any and all liabilities, obligations, claims, demands,
damages, penalties, causes of action, losses, fines, costs and expenses
(including without limitation reasonable attorneys' fees and expenses) imposed
upon or incurred by Lender arising from, or in connection with, directly or
indirectly, this Agreement, except to the extent arising solely out of the
willful misconduct or gross negligence of Lender. This indemnity is in addition
to any other indemnity agreements made by Borrower to Lender in the Mortgage,
the Note or in any of the other Loan Documents. Borrower covenants and agrees
that, in performing any of its duties under this Agreement, neither Lender nor
any of its successors or assigns shall be liable for any losses, costs or
damages which may be incurred by any of them as a result thereof, except for any
losses, costs or damages arising out of the willful misconduct or gross
negligence of such party.

     8. FEES AND COSTS. Borrower shall pay Lender at the closing of the Loan a
one time administrative fee of $500.00 for its services in administering the
Reserve. In addition, Borrower shall reimburse Lender within ten (10) days after
demand all reasonable fees, charges, costs and expenses incurred by Lender in
connection with all inspections made by Lender or Lender's representatives in
carrying out Lender's responsibility to make certain determinations under this
Agreement.

     9. MISCELLANEOUS.

          (a) Except as otherwise expressly provided herein, in any instance
     where the consent or approval of Lender is required or may be given or
     where any determination, judgment or decision is to be rendered by Lender
     under this Agreement, such approval and consent shall be given or withheld
     in Lender's sole and absolute discretion.

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                                                          JHREF Loan No. 3212525

          (b) All notices hereunder shall be given in accordance with the
     provisions of the Mortgage, except all notices hereunder to Lender shall be
     given to the following address: John Hancock Real Estate Finance, Inc.,
     John Hancock Place, 200 Clarendon Street, Boston, Massachusetts 02116,
     Attn: Mary Lou Staples, Loan Number 3212525.

          (c) This Agreement shall be binding upon Borrower and its heirs,
     devisees, representatives, successors and assigns, including successors in
     interest of Borrower in and to all or any part of the Mortgaged Property,
     and shall inure to the benefit of and may be enforced by Lender and its
     heirs, successors, legal representatives, substitutes and assigns. Borrower
     shall not assign any of its rights or obligations under this Agreement.

          (d) This Agreement is intended solely for the benefit of Borrower and
     Lender, and no third party shall have any right or interest in this
     Agreement, nor any right to enforce this Agreement against any party
     hereto.

          (e) This Agreement contains the complete and entire understanding of
     the parties with respect to the matters covered and may not be modified,
     amended, waived, extended, changed, discharged or terminated orally or by
     any act or failure to act on the part of Borrower and Lender, but only by
     an agreement in writing signed by the party against whom the enforcement of
     any modification, amendment, waiver, extension, change, discharge or
     termination is sought.

          (f) No provision of this Agreement or action taken by Lender pursuant
     hereto shall be construed as acceptance or approval by Lender of any Tenant
     Improvement or an acknowledgment that the Tenant Improvement has been
     completed in accordance with applicable building, zoning or other codes,
     ordinances, statutes, laws, regulations or requirements of any governmental
     authority. Each and every provision for the consent, approval, inspection,
     review or verification by Lender hereunder is for Lender's own purpose and
     benefit only, and no other party may require that the same be given or be
     entitled to assume that Lender shall refuse to make or give the same. In
     addition, in no event shall any term hereof, or any action taken by Lender
     contemplated hereby, be deemed to be or construed as a warranty or
     representation by Lender as to the adequacy of any Tenant Improvement, nor
     that the same complies with applicable laws (including, without limitation,
     any and all environmental laws and laws for the handicapped and/or
     disabled).

          (g) Borrower hereby covenants that Borrower shall not further pledge,
     assign or grant a security interest or any other interest in or to, the
     Reserve or the Account, or any proceeds, replacement or substitutes
     thereto.

          (h) No right or remedy conferred upon or reserved to Lender under this
     Agreement is intended to be exclusive of any other right or remedy, and
     each and every such right and remedy shall be cumulative and concurrent and
     may be enforced separately, successively or together, and may be exercised
     from time to time as often as may be deemed necessary by Lender.

          (i) Nothing herein or in the Loan Documents is intended to create, nor
     creates, nor shall be deemed to create, a joint venture, partnership,
     tenancy-in-common, or joint tenancy 

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                                                          JHREF Loan No. 3212525

     relationship between Borrower and Lender, nor to grant Lender any interest
     in the Mortgaged Property other than that of creditor or mortgagee.

          (j) If any provisions of this Agreement shall conflict with any
     provisions of the other Loan Documents regarding the Funds, the provisions
     contained in this Agreement shall control.

          (k) If any term, covenant or condition of this Agreement is held to be
     invalid, illegal or unenforceable in any respect, this Agreement shall be
     construed without such provision.

          (l) This Agreement shall be governed by and construed in accordance
     with the laws of the State of New Hampshire and the applicable laws of the
     United States of America.

          (m) This Agreement may be executed in multiple counterparts, each of
     which when taken together shall constitute one and the same original.




    [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK; SIGNATURE PAGE(S) FOLLOW(S)]


                                        6

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     IN WITNESS WHEREOF, Borrower and Lender have executed this Agreement as of
the date first above written.

                                   BORROWER:

Witnessed By:                      BIRCH POND REALTY CORPORATION
                                   (doing business in the State of New Hampshire
                                   as BPRC)



                                   By: /s/Olga L. Conley
                                      ------------------------------------------
Name: Katherine Culkin             Name: Olga L. Conley
     ----------------------        Its: Treasurer
                                   Borrower's Social Security or Taxpayer
                                   Identification Number: 02-0506310

Name:



                                   LENDER:

                                   JOHN HANCOCK REAL ESTATE
                                   FINANCE, INC.,
                                   A DELAWARE CORPORATION


                                   By:  /s/ Timothy A. Roseen       
                                      ------------------------------------------
                                   Name:    Timothy A. Roseen
                                        ----------------------------------------
                                   Title:   Vice President
                                         ---------------------------------------


                                        7

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                             SCHEDULES AND EXHIBITS


Schedule 1 - Monthly Deposits



[Exhibit A - Specific Lease]



                                        1

<PAGE>



                                   SCHEDULE 1

                                MONTHLY DEPOSITS



The amount of each monthly deposit is Eight Thousand Four Hundred Dollars
($8,400.00).


                                  Schedule 1-1

<PAGE>



                                   SCHEDULE 3
                           REQUEST FOR RELEASE (NO. )


TO:      JOHN HANCOCK REAL ESTATE FINANCE, INC. ("LENDER")

FROM:   ("BORROWER")


     This Request for Release is submitted by Borrower in accordance with the
Tenant Improvement and Leasing Commissions Agreement dated as of           ,
199-, between Borrower and Lender (the "AGREEMENT"). Terms used with initial
capital letters and not defined in this Disbursement Request have the meanings
given them in the Agreement.


     Borrower hereby requests disbursement for the payment of the Tenant
Improvements (or a portion thereof) in the amounts specified below:


COST OF TENANT IMPROVEMENTS (include quantity,            AMOUNT/PRICE
materials and labor)

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


TOTAL DISBURSEMENT REQUESTED                              $
                                                           ---------------------

     1. Borrower hereby requests disbursement for the payment of leasing
commissions in the amount specified below:

AMOUNT OF LEASING COMMISSIONS                                 LEASING AGENT

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

     2. Borrower certifies, represents and warrants to Lender that all
statements, invoices, bills, costs, expenses and any other sums of money owing
with respect to the Tenant Improvement and Leasing Commissions incurred on or
before this date have been paid in full in the amounts, if any, described on
ANNEX 1 hereto. The estimated costs of completing the uncompleted Tenant
Improvements as of this date are as described on a line item basis on ANNEX 1.


                                  Schedule 3-1

<PAGE>



     3. Borrower certifies, represents and warrants to Lender that (a) Borrower
is entitled to a disbursement of the Reserve for the items and amounts requested
in Section 1 above pursuant to the Agreement; (b) Borrower's representations and
warranties made in the Loan Documents and the Agreement are true and correct on
and as of this date; (c) no Event of Default nor any event which with the giving
of notice or the lapse of time, or both, would become an Event of Default, has
occurred and (d) the Tenant Improvement and Leasing Commissions listed in
Sections 1 and 2 above have been fully paid for, and no claim or claims exist
against the Borrower or against the Mortgaged Property out of which a lien based
on a leasing commission or furnishing labor or material exists or might ripen.

         Date:______________, 199___.


                                     BORROWER:

                                     By:
                                        ----------------------------------------
                                     Name:
                                          --------------------------------------
                                     Title:
                                           -------------------------------------

     SWORN TO AND SUBSCRIBED BEFORE ME by ______________________,

this________ day of_____________, 199__.


                                       -----------------------------------------
                                       Notary Public           (Seal)
                                       Name (Print):
                                                    ----------------------------

My Commission Expires:
Initial Approval -- Name:                             Date: 
                         -------------------               --------------------.

Disbursement Approval -- Name:                         D  a  t  e
                              -----------------

                                  Schedule 3-2

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                                     ANNEX 1


TENANT IMPROVEMENTS                AMOUNTS PAID               ESTIMATED COSTS OF
                                                                  COMPLETION








         LEASING COMMISSIONS                         AMOUNTS PAID








<PAGE>


                                    EXHIBIT A

                                [SPECIFIC LEASE]


1.   Lease dated March 1, 1999 between DM Management Company and Birch Pond
Realty Corporation.



                                  Schedule 3-2