<PAGE>
 
                              TWO WISCONSIN CIRCLE



                         ADDENDUM NO. 7 TO OFFICE LEASE
                         ------------------------------


          THIS ADDENDUM NO. 7 TO OFFICE LEASE (this "Addendum") is made and
entered into this 24th day of July, 1998, by and between TWO WISCONSIN CIRCLE
JOINT VENTURE, a Maryland joint venture, hereinafter called "Lessor," and
HEALTHCARE FINANCIAL PARTNERS, INC., formerly known as Health Partners Financial
Corporation, a Delaware corporation, hereinafter called "Lessee."

                                   WITNESSETH:

          WHEREAS, by Office Lease dated the 4th day of January 1996, as amended
by Addendum No. 1 to Office Lease dated the 26th day of July 1996, Addendum No.
2 to Office Lease dated the 13th day of August 1996, Addendum No. 3 to Office
Lease dated the 17th day of July 1997, Addendum No. 4 to Office Lease dated the
27th day of February, 1998, Addendum No. 5 to Office Lease also dated the 27th
day of February, 1998, and Addendum No. 6 to Office Lease dated the 17th day of
July, 1998 (as so amended, the "Lease"), Lessor currently leases to Lessee
approximately 21,820 square feet of rentable area on the fourth (4th) floor, and
approximately 2,201 square feet of rentable area on the eighth (8th) floor
(collectively, the "Existing Demised Premises"), in the building situated at
Two Wisconsin Circle, Chevy Chase, Maryland (the "Building"); and

          WHEREAS, Lessor and Lessee desire to expand the Existing Demised
Premises by adding thereto and incorporating therein, upon the terms and
conditions hereinafter set forth, additional space on the seventh (7th) floor of
the Building comprising approximately 17,261 square feet of rentable area and
being the entirety of the seventh (7th) floor (the "Additional Space").

          NOW, THEREFORE, in consideration of the mutual covenants and
agreements hereinafter set forth, the parties hereto do mutually agree that the
Lease shall be and is hereby amended to provide as follows, all capitalized
terms being as defined in the Lease unless otherwise noted herein:


1.        ADDITIONAL SPACE
          ----------------

          There is hereby added to the Existing Demised Premises, and Lessor
does hereby lease to Lessee, and Lessee does hereby lease from Lessor, the
Additional Space, subject to and upon all of the terms and conditions of the
Lease, as amended hereby, to the end that the Demised Premises under the Lease
shall be the said approximately 21,820 square feet of rentable area on the
fourth (4th) floor of the Building, the said approximately 2,201 square feet of
rentable area on the eighth (8th) floor of the Building, as well as the said
approximately 17,261 square feet of rentable area on the seventh (7th) floor of
the Building, as such seventh (7th) floor space is outlined on the floor plan
attached hereto and made a part hereof as Exhibit A.
                                          ---------
<PAGE>
 
2.        TERM AND RENEWAL
          ----------------

          (A) The Additional Space shall be added to the Existing Demised
Premises on the Addition Date, which shall be the earlier of (i) Lessee's
occupancy of the Additional Space for the conduct of its business, or (ii) sixty
(60) days after the Possession Date, which shall be the date Lessor has
confirmed to Lessee in writing that the existing tenant of the Additional Space
has vacated the same and possession thereof is thereby delivered to Lessee for
the purpose of enabling Lessee to undertake its Pre-occupancy Tenant Work (as
defined below). The Possession Date is currently anticipated to occur on or
about November 1, 1998, thereby resulting in an outside Addition Date on or
about January 1, 1999. The term of the Lease as to the Additional Space shall
expire on the last day of the calendar month during which the fifth (5th)
anniversary of the Addition Date occurs, and the initial term of the Lease as to
the Existing Demised Premises shall be extended accordingly as hereinafter
provided, to the end that the initial term of the Lease as to both the
Additional Space and the Existing Demised Premises (other than the said eighth
(8th) floor space which Lessee occupies on a month-to-month basis) shall be
coterminous for all purposes.

          (B) Pursuant to the terms of the said Addendum No. 3 to Office Lease.
the initial term of the Lease has heretofore been extended and renewed to expire
on the 17th day of December 2002. Effective upon and subject to occurrence of
the Possession Date, the initial term of the Lease shall be and is hereby
further extended and renewed for a period to expire on the last day of the
calendar month during which the fifth (5th) anniversary of the Addition Date
occurs, subject to further extension pursuant to Section 35 of the Lease. Upon
the Addition Date, Lessor and Lessee shall execute the "Declaration as to
Addition Date" attached hereto as Exhibit B, which shall specify both the
Addition Date and the expiration date of the initial term of the Lease as so
extended and renewed.

          (C) It is understood and agreed that the obligations of Lessor and
Lessee under this Addendum are contingent upon the existing tenant of the
Additional Space vacating and surrendering full possession of the same on or
about October 31, 1998. In the event Lessor is unable to deliver possession of
the Additional Space on the anticipated Possession Date, because the existing
tenant has failed to so vacate, Lessor shall not be liable or responsible for
any claims, damages or liability arising in connection therewith or by reason
thereof, nor shall Lessee be excused or released from the Lease, as amended
hereby, because of Lessor's inability to deliver possession of the Additional
Space on that date. The Addition Date, however, shall be extended to the earlier
of (i) the date the Additional Space is occupied by Lessee for the conduct of
its business, or (ii) the date which is sixty (60) days after the date Lessor
has notified Lessee in writing that the existing tenant has vacated the
Additional Space and possession thereof is available to Lessee; provided,
however, that if the existing tenant fails to vacate and surrender full
possession of the Additional Space on or before December 31, 1998, then either
Lessor or Lessee shall have the right to cancel and terminate this Addendum
without further liability by giving written notice of such cancellation and
termination to the other on or before January 15, 1999, and this Addendum shall
be null and void and of no further force or effect upon the delivery of such
notice. Lessor shall endeavor to keep Lessee informed as to the status of its
efforts to recapture possession of the Additional Space from the existing
tenant.

                                      -2-
<PAGE>
 
3. RENT
   ----

          The additional monthly rent for the Additional Space (hereinafter
referred to as "Additional Monthly Rent"), which Lessee hereby agrees to pay in
advance to Lessor and Lessor hereby agrees to accept, shall be as follows:

<TABLE> 
<CAPTION> 

          Lease Period                                                      Additional Monthly Rent
          ------------                                                      -----------------------
          <S>                                                               <C> 
          From the Addition Date through
          December 31, 1999                                                        $46,029.33

          From January 1, 2000 through
          December 31, 2001                                                        $47,467.75

          From January 1, 2001 through
          December 31, 2002                                                        $48,906.17        

          From January 1, 2002 through
          December 31, 2003                                                        $50,344.58

          From January 1, 2003 through
          the expiration of the
          initial term of the Lease                                                $51,783.00

</TABLE> 

If the Addition Date is a date other than the first day of a calendar month, the
Additional Monthly Rent from such date until the first day of the following
calendar month shall be prorated at the rate of one-thirtieth (1/30th) of the
Additional Monthly Rent for each day, payable in advance. Additional Monthly
Rent as specified above shall be payable as additional rent under the Lease, as
amended hereby, simultaneously with each payment of Monthly Rent in advance on
the first day of each calendar month during the term of the Lease, as hereby
extended and renewed.


4.        RENTAL ESCALATION FOR INCREASES IN EXPENSES
          -------------------------------------------

          In the event the Operating Expenses of the Building during any
calendar year commencing January 1, 2001 and thereafter exceed the amount of
"Base Operating Expenses," defined to be the amount of Operating Expenses
actually incurred by Lessor in calendar year 2000, Lessee shall pay to Lessor,
as additional rent, Lessee's proportionate share (allocable only to the
Additional Space, not the Existing Demised Premises) of the portion of the
Operating Expenses that exceeds the amount of the Base Operating Expenses. The
proportionate share to be so paid by Lessee shall be the percentage which the
total square feet of the Additional Space bears to the total square feet of all
office and retail space in the Building, which is 7.78%, and the amount of said
proportionate share to be paid by Lessee shall be the same proportion as the
number of days in such calendar year the Additional Space was leased by Lessee
bears to three hundred sixty (360). The term "Operating Expenses" is defined as
meaning (i) any and all

                                      -3-
<PAGE>
 
expenses, charges and fees incurred in connection with managing, operating,
maintaining, servicing, insuring and repairing the Building and related exterior
appurtenances, and (ii) Real Estate Taxes and impositions, general and special,
of whatever kind or description levied against the Building or land. The term
"Real Estate Taxes" for any calendar year is hereby defined to mean the total
amount of all taxes and assessments, general and special, ordinary and
extraordinary, foreseen and unforeseen, now or hereafter assessed, levied or
imposed upon the Building and the land on which the Building is situated ("the
Land") for such year, together with any tax in the nature of a real estate tax,
and ad valorem tax on rent or any tax on income if imposed in lieu of or in
addition to real estate taxes and assessments, and any taxes and assessments
which may hereafter be substituted for Real Estate Taxes and together with the
amount of any fees incurred in the setting of the amount of these taxes. In the
event that the method currently used for the computation of the assessed market
value of the Building and/or the Land is discontinued or revised, the
determination of the increases in Real Estate Taxes under this Section 4 shall
thereafter be made according to a formula and procedure which most nearly
approximates the method of determination hereinabove set forth. In the event
that any business, rent, or other taxes which are now or hereafter levied upon
Lessee's use or occupancy of the Additional Space, on Lessee's leasehold
improvements therein, on Lessee's business at the Additional Space or on Lessor
by virtue of Lessee's occupancy of the Additional Space, are enacted, changed or
altered so that any such taxes are levied against Lessor or in the event that
the mode of collection of such taxes is changed so that Lessor is responsible
for collection or payment of such taxes, any and all such taxes shall be deemed
to be a part of the increase in Real Estate Taxes and Lessee shall pay Lessor
Lessee's proportionate share of the full amount of such taxes. Operating
Expenses shall not include the Operating Costs listed in the next paragraph
below, nor shall Operating Expenses include the cost of capital improvements
(unless such improvements are reasonably expected to reduce the expenses of the
Building or are made to comply with governmental requirements imposed after the
date of this Addendum, in which event the cost of any such improvement amortized
over the life of the improvement will be included in Operating Expenses),
painting or decoration other than public areas, interest and amortization of
mortgages, depreciation of the Building, or compensation paid to officers or
executives of the Lessor or its Management Agent (as defined in Section 29 of
the Lease).

          In the event the Operating Costs of the Building during any calendar
year commencing January 1, 2001 and thereafter exceed the amount of "Base
Operating Costs," defined to be the amount of Operating Costs actually incurred
by Lessor in calendar year 2000, Lessee shall pay to Lessor, as additional rent,
Lessee's proportionate share (allocable only to the Additional Space, not the
Existing Demised Premises) of the portion of the Operating Costs that exceeds
the amount of the Base Operating Costs. The term "Operating Costs" is defined as
meaning the costs of the cleaning contract and cleaning supplies, and
electricity for the Building. The proportionate share to be so paid by Lessee
shall be the percentage which the total square feet of the Additional Space
bears to the total square feet of all office space in the Building, which is
8.38% and the amount of said proportionate share to be paid by Lessee shall be
the same proportion as the number of days in the calendar year the Additional
Space was leased by Lessee bears to three hundred sixty (360). In the event
Lessor installs a separate electric meter or meters for the premises occupied by
any other tenant or tenants of the Building, an appropriate adjustment as
reasonably determined by Lessor will be made in the electricity cost component
of Operating Costs for the tenants of the Building not separately metered.

                                      -4-
<PAGE>
 
          As soon as practicable after the first day of January, 2001, and as
soon as practicable after each first day of January thereafter during the term
of the Lease, as hereby extended and renewed, Lessor shall submit to Lessee a
statement of Lessor's estimate of the amount by which Operating Expenses and
Operating Costs for the applicable calendar year (as estimated by Lessor) are
expected to exceed the amount of the Base Operating Expenses and the Base
Operating Costs, respectively. Commencing with the first day of the month
immediately following the delivery of such statement, Lessee will pay to Lessor,
as additional rent with Monthly Rent and the Additional Monthly Rent,
one-twelfth (1/12th) of Lessee's proportionate share of such excess of estimated
Operating Expenses and Operating Costs over Base Operating Expenses and Base
Operating Costs, respectively. Lessee shall continue to make said payment
monthly thereafter on the first day of each calendar month until the amount of
such payment is next adjusted after January 1st of the following calendar year
for increases in the amounts of Lessee's proportionate share of Operating
Expenses and/or Operating Costs as provided for herein.

          As soon as practicable after the expiration of each applicable
calendar year, a determination shall be made of the Operating Expenses and
Operating Costs for such calendar year and the amount of the increase (if any)
in the Operating Expenses and Operating Costs for such calendar year over the
amount of the Base Operating Expenses and the Base Operating Costs respectively.
Operating Expenses and Operating Costs for each calendar year shall be those
actually incurred, provided, however, that if the Building was not at least
eighty-five percent (85%) occupied during the entire calendar year, the
Operating Expenses and Operating Costs shall be adjusted to project the
Operating Expenses and Operating Costs as if the Building were eighty-five
percent (85%) occupied. Lessor shall submit to Lessee a statement of the
aforesaid determination, including Lessee's aforesaid proportionate share of any
increase.

          Within thirty (30) days after the delivery of such statement
(including any statement delivered after the expiration or termination of the
term of the Lease, as hereby extended and renewed), Lessee shall pay to Lessor
an amount equal to (i) its proportionate share of the increase, if any, in the
actual amount of Operating Expenses and/or Operating Costs for the just expired
calendar year over the Base Operating Expenses and the Base Operating Costs,
respectively, less (ii) the aggregate amount of monthly payments toward
additional rent made by Lessee during such calendar year and attributed to the
estimated increases in Operating Expenses and/or Operating Costs for such
calendar year. If the aggregate amounts of such payments toward additional rent
for estimated increases in Operating Expenses and/or Operating Costs paid by
Lessee during such calendar year exceeds Lessee's proportionate share of the
actual increases in Operating Expenses and/or Operating Costs, the excess shall
be credited toward payment of the next installment of Monthly Rent to be paid by
Lessee after Lessee receives said statement of Operating Expenses and Operating
Costs from Lessor, or, in the event the term of the Lease, as hereby extended
and renewed, has previously expired or been terminated, such excess shall be
refunded to Lessee within thirty (30) days after the delivery of such statement,
less such portion of such excess as Lessor shall have retained to cure any
default by Lessee under the Lease, as amended hereby or as subsequently amended.

                                      -5-
<PAGE>
 
5.        PRE-OCCUPANCY TENANT WORK
          -------------------------

          The Additional Space has been previously occupied, and it is
acknowledged that Lessor has heretofore completed tenant work within the
Additional Space substantially in accordance with the provisions of Exhibit B of
                                                                    ---------
the Lease. Lessee shall accept the Additional Space "as is" upon the Possession
Date, and Lessor shall have no obligation to furnish or install any items
whatsoever of tenant work within the Additional Space. All tenant work and
installations desired by Lessee for its occupancy of the Additional Space
("Pre-occupancy Tenant Work") shall be undertaken by Lessee at its cost and
expense pursuant to Section 9 of the Lease, subject to the Tenant Allowance as
hereinafter defined and provided.

          Lessor shall pay to Lessee, on the following terms and conditions, a
cash allowance of up to Two Hundred Fifty-Eight Thousand Nine Hundred Fifteen
and 00/l00ths Dollars ($258,915.00) (the "Tenant Allowance") to be applied to
the cost of completion of the Preoccupancy Tenant Work undertaken by Lessee in
the Additional Space concurrent with its initial occupancy thereof (exclusive of
movable trade fixtures and equipment). The Tenant Allowance shall be disbursed
as the Pre-occupancy Tenant Work progresses and upon Lessee's submission of a
requisition statement not more frequently than monthly and within six (6) months
following the Possession Date, with supporting invoices representing the cost of
all Pre-occupancy Tenant Work since the last requisition, together with evidence
of payment of the cost of all Preoccupancy Tenant Work covered by the last
requisition. If requested by Lessor, Lessee shall also submit lien waivers by
all contractors or suppliers employed by Lessee. Lessor shall have the right to
verify all such invoices, and after inspection and approval by Lessor or its
architect of the Pre-occupancy Tenant Work, which inspection and/or approval
shall not be unreasonably withheld or delayed, Lessor shall pay to Lessee an
amount equal to the approved requisitioned sum; provided, however, that in no
event shall Lessor's total liability for such payments exceed the Tenant
Allowance, and in no event shall Lessor have any liability to disburse any sum
pursuant to a requisition statement submitted later than six (6) months
following the Possession Date.


6.        ADDITIONAL DEPOSIT
          ------------------

          Lessor currently holds the sum of Sixty-Thee Thousand One Hundred
Twenty-One and 42/100 Dollars ($63,121.42) as a non-interest bearing cash
security deposit under the Lease. Upon the Possession Date under this Addendum
and as a condition to delivery of possession of the Additional Space, Lessee
shall deposit with Lessor the additional sum of Fifty-One Thousand Seven Hundred
Eighty-Three and 00/l00ths Dollars ($51,783.00). The resulting sum in the
amount of One Hundred Fourteen Thousand Nine Hundred Four and 42/100ths Dollars
($114,904.42) shall continue to be held by Lessor as a non-interest bearing cash
security deposit under the Lease, as amended hereby, pursuant to and in
accordance with the provisions of Section 6 of the Lease. If Lessor elects to
apply all or any portion of the increased cash deposit to cure Lessee's default,
Lessee shall be obligated to promptly deposit with Lessor cash in an amount
sufficient to restore the cash security deposit to One Hundred Fourteen Thousand
Nine Hundred Four and 42/100ths Dollars ($114,904.42).

                                      -6-
<PAGE>
 
7.        LEASE PROVISIONS APPLICABLE
          ---------------------------

          All of the terms and conditions of the Lease, as amended or
supplemented hereby, shall be applicable to the Additional Space hereby added to
the Existing Demised Premises. Once added to the Existing Demised Premises, the
Additional Space shall be deemed to be a part of the premises demised under the
Lease for all purposes. All terms and conditions of the Lease, as amended or
supplemented hereby, are hereby ratified and affirmed and shall remain in full
force and effect.

          IN WITNESS WHEREOF, Lessor and Lessee have caused this Addendum to be
signed in their names by their duly authorized representatives and delivered as
their act and deed, intending to be legally bound by its terms and provisions.

                                     LESSOR:

                                       TWO WISCONSIN CIRCLE JOINT VENTURE,
                                       a Maryland joint venture


Attest:                                By:  The Chevy Chase Land Company of
                                            Montgomery County, Maryland, a
                                            General Partner


/s/ David G. Dolan                          By:/s/ Edward Hall Asher
------------------------------                 -------------------------------
Vice President                                 Name: Edward Hall Asher
(SEAL)                                         Title: President

STATE OF MARYLAND
COUNTY OF MONTGOMERY, ss:

     I, Susan L. Exclesheimer  a Notary Public in and for the State of Maryland,
        ----------------------
do hereby certify that Edward Hall Asher , who is personally well known to me as
                       ------------------
the person who executed the foregoing and annexed Addendum, dated the 24th  day
                                                                      -----
of July, 1998, on behalf of the Lessor, to acknowledge the same, personally
appeared before me in said jurisdiction and acknowledged said Addendum to be the
act and deed of The Chevy Chase Land Company of Montgomery County, Maryland, as
a general partner of and for and on behalf of the Lessor, and delivered the same
as such.

     GIVEN under my hand and seal this 24th  day of July , 1998.
                                       -----        ----- 

                                        Susan L. Exclesheimer
                                        ------------------------------
My Commission Expires 8/1/00            Notary Public

                   (Signatures Continue on the Following Page)

                                      -7-
<PAGE>
 
                                     LESSEE:

Attest:                              HEALTHCARE FINANCIAL PARTNERS, INC., 
                                     a Delaware corporation



/s/ [SIGNATURE ILLEGIBLE]            By: /s/ Edward P. Noldberg, Jr.
----------------------------            -------------------------------
Secretary                               Name: Edward P. Noldberg, Jr.
(SEAL)                                  Title: EVP



STATE OF MARYLAND
COUNTY OF MONTGOMERY, ss:

          I, ELLEN M. GOTT, a Notary Public in and for the State of Maryland,
             --------------
do hereby certify that EDWARD P. NOLDBERG, JR., who is personally well known to
                       ------------------------
me as the person who executed the foregoing and annexed Addendum, dated the
______ day of July, 1998, on behalf of the Lessee, to acknowledge the same,
personally appeared before me in said jurisdiction and acknowledged said
Addendum to be the act and deed of Healthcare Financial Partners, Inc. and
delivered the same as such.

                                                        
          GIVEN under my hand and seal this  24th, day of July, 1998.
                                            -----         ----

                                           /s/ Ellen M. Gott
                                           -------------------------------
                                           Notary Public

My Commission Expires                              ELLEN M. GOTT
                                           NOTARY PUBLIC STATE OF MARYLAND
                                         My Commission Expires July 21, 2001

                                      -8-
<PAGE>
 
--------------------------------------------------------------------------------





                      [BUILDING FLOOR PLAN APPEARS HERE]



                                Sq.Ft.: 17,261
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
2 Wisconsin Circle                                                 Chevy Chase
  Seventh Floor                                                    Land Company
                                                                   301-986-8809
--------------------------------------------------------------------------------

                                      -9-
<PAGE>
 
                             TWO WISCONSIN CIRCLE

                                  EXHIBIT "B"

                        DECLARATION AS TO ADDITION DATE


          Attached to and made a part of the Addendum No. 7 to Office Lease,
dated the ______ day of July, 1998, entered into by and between Two Wisconsin 
Circle Joint Venture, as Lessor, and Healthcare Financial Partners, Inc., as 
Lessee.

          Lessor and Lessee do hereby declare and evidence that possession of
the Additional Space was accepted by Lessee on the ________ day of _________,
1998 and either Lessee has occupied the Additional Space for the conduct of its
business or sixty (60) days has expired. Accordingly, the Addition Date is
established as being the ______ day of________, 199_ , and the initial term of
the Lease, as extended and renewed by the said Addendum, shall expire on the
_____ day of _________, 200_. 

LESSEE:                                  LESSOR:

HEALTHCARE FINANCIAL                     TWO WISCONSIN CIRCLE JOINT VENTURE
PARTNERS, INC.

                                         By: The Chevy Chase Land Company of
                                             Montgomery County, Maryland

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


                                      B-1