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                                                                   Exhibit 10.13

                                 S U B L E A S E

         THIS SUBLEASE made as of February 9, 1999, by and between ADVANCED
HEALTH CORPORATION, having an office at 555 White Plains Road, Tarrytown, New
York 10597 (hereinafter called "Sublessor") and WESTCO ASSOCIATES, INC., having
an office at 3 Browns Lane, Suite 203, Hawthorne, New York 10532 (hereinafter
called "Subtenant"),

                              W I T N E S S E T H:

         WHEREAS, Sublessor is the tenant in possession pursuant to the First
Amendment to Lease Agreement dated September 20, 1996 and certain other prior
leases referenced therein (together, the "Prime Lease", a copy of which is
annexed hereto as Exhibit A) between Reckson Operating Partnership, L.P. (as
landlord) and Sublessor (as tenant) pursuant to the provisions of which
Sublessor now subleases that part of the fifth (5th) floor comprising twenty-six
thousand three hundred and two (26,302) square feet located in the building
known as 555 White Plains Road, Tarrytown, New York (the "Premises"); and

         WHEREAS, Sublessor wishes to sublease to Subtenant a portion of said
5th floor constituting eight thousand seven hundred fifty (8,750) square feet as
shown as shaded area on the diagram annexed hereto as Exhibit B (the "Sublet
Premises") pursuant to the provisions of this Sublease, hereinafter set forth;

         NOW, THEREFORE, Sublessor and Subtenant, in consideration of the
charges, covenants and agreements hereinafter set forth, mutually covenant and
agree as follows:

         1. Sublease. Sublessor hereby leases the Sublet Premises to Subtenant
for occupancy during the Term.

         2. Term. The term of this Sublease shall commence on the date after the
date that Reckson Operating Partnership, L.P., the present landlord under the
Prime Lease ("Landlord"), shall have given its written consent to this Sublease
("Commencement Date"), and shall terminate on March 31, 2002, unless earlier
terminated as provided herein (the "Term"). The obligation to pay rent shall
commence ("Rent Commencement Date") seventy-five (75) days after the issuance of
the work permits and approvals necessary to build out the space in accordance
the plan attached as Exhibit C (the "Build-out"). If the Prime Lease or the term
thereby granted is terminated for any reason whatsoever, this Sublease shall
thereupon simultaneously terminate and thereupon, except as otherwise herein
specifically provided, the obligations of the Sublessor and Subtenant, other
than the obligations of Subtenant for payment of any monies then owing to
Sublessor, shall cease, except that the parties shall remain liable for any
obligations incurred prior to any such termination date for any matter occurring
prior to such date.

         3. Annual Fixed Rent. Subtenant shall pay Sublessor fixed rent for the
Sublet Premises, inclusive of all charges for electricity, except as described
below, at the annual rate of one hundred eighty one thousand five hundred
sixty-two dollars and fifty cents ($181,562.50) for the period ending March 31,
2000 (the "First Rent Period") and thereafter at the annual rate of one hundred
ninety six thousand ($196,000.00) dollars. Fixed rent shall 
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be paid in twelve (12) equal monthly installments in advance, each in the amount
of fifteen thousand one hundred thirty dollars and twenty one cents
($15,130.21), for the First Rent Period except as otherwise provided below in
paragraph 3, and thereafter in equal monthly payments of sixteen thousand three
hundred thirty-three dollars and thirty-three cents ($16,333.33) and without
notice or demand, on the 1st day of the month for which the fixed rent payment
is due during the term hereof, and without setoff, deduction or abatement.
Should Landlord charge Sublessor fees for excess electrical usage due to
subtenant's electrical usage, subtenant shall pay Sublessor such difference. All
installments of fixed rent shall be paid by check, drawn on a member bank of the
New York Clearinghouse Association, to the order of Sublessor and shall be
delivered or mailed to Sublessor at its address first above set forth, or at
such other address as Sublessor may from time to time in writing designate. If
the date on which Subtenant's obligation to pay fixed rent or additional rent
shall commence on a date other than the first day of a calendar month or shall
end on a date other than the last day of a calendar month, then the fixed rent
and additional rent payable by Subtenant shall be apportioned based upon the
portion of such calendar month included with the term of this Sublease. The
foregoing notwithstanding, the first thirty-four thousand dollars ($34,000.00)
of fixed rent otherwise payable hereunder is abated so that Subtenant shall
enjoy a free rent period of approximately two months and eight days from and
after the Rent Commencement Date. Upon execution hereof, Subtenant will pay
Sublessor the first monthly installment of fixed rent payable under this
Sublease.

         4. Use. The Sublet Premises shall be used by Subtenant solely for
executive and administrative offices and for no other purpose.

         5. Condition of the Sublet Premises and Commencement of Construction.
Subtenant has examined, and agrees to accept, the Sublet Premises in the
condition and state of repair existing on the date of the execution of this
Sublease, subject to Subtenant's receipt of consent from Landlord to the
Build-out. Construction shall commence upon receipt of Landlord's consent and
the receipt by Subtenant or its contractor and agents of work permits and
approvals required for such construction. Subtenant warrants that it will seek
to obtain all necessary permits and approvals without delay.

         6. Telephones and Equipment. Subtenant shall install its telephone and
facsimile system and equipment in the Sublet Premises at its sole expense and
shall have the sole obligation to maintain and repair same during the Term.

         7. Measurements. Subtenant and its representatives shall have the right
to inspect and to take measurements of the Sublet Premises during business hours
effective immediately after this Sublease is executed except that existing
facilities and equipment shall not be disturbed.

         8. Brokerage. Sublessor agrees to pay the commissions earned by any and
all brokers that were the procuring cause of the parties hereto entering into
this sublease. Such brokers shall be compensated per separate agreement.


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         9. Subordination. This Sublease is subject and subordinate to the
rights of Landlord under the Prime Lease to any renewal, amendments, or
modification thereof, to the rights of any mortgagee under any mortgage to which
the Prime Lease or said Sublease is subject or subordinate, to all renewals,
modifications, consolidations, correlations, replacements and extensions
thereof, and to any Ground Lease to which the Prime Lease or said Sublease is
subject or subordinate, and to all renewals, modifications, consolidations,
amendments, replacements and extensions thereof. The provisions for such
subordination shall be self-operative so that no further instrument of
subordination need be required by any mortgagee.

         10. Prime Lease. This Sublease is subject to all of the convenants,
agreements, terms, provisions and conditions contained in the Prime Lease which
are hereby made a part of this Sublease with the same force and effect as if
they were fully set forth herein. Wherever the term "Tenant" appears in the
Prime Lease, it shall read "Subtenant" and where ever the term "Owner" appears,
it shall be deemed to include "Sublessor" unless by its terms such use would be
inappropriate and Sublessor shall have all the rights and remedies of Landlord
thereunder, without limiting Sublessor's rights and remedies to enforce any
provision of this Sublease not contained in the Prime Lease. Subtenant agrees to
observe and perform all of such covenants, agreements, terms, provisions and
conditions contained in this Sublease as though and as if Subtenant was the
tenant originally named in the Prime Lease, except that the provisions of the
Prime Lease which have been specifically addressed by this Sublease shall not,
to the extent addressed, apply and Subtenant shall not be obligated thereunder
except as otherwise provided in this Sublease. The foregoing notwithstanding,
Subtenant shall pay to Sublessor as additional rent its pro rata share of
increases in Base Impositions and Base Operating Costs due to Landlord from
Sublessor. The term "Base Impositions" shall mean the Impositions levied against
the property of which the demised premises are part for city and school taxes
for the 1999 state, county and town year and for the 1998/1999 school year. The
term "Base Operating Costs" shall mean the Operating Costs in effect for the
calendar year ending December 31, 1999. The Subtenant's pro rata share shall
equal 33.27% of the Tenant Proportionate share. Subtenant shall also be
allocated four (4) parking spaces. Sublessor shall have no obligation to provide
any services or to do any act or thing with respect to the Sublet Premises which
are the obligation or responsibility of the Landlord under the Prime Lease, and
Subtenant agrees to look solely to Landlord under the Prime Lease for the
provision of any such service and observance and performance of any such act or
thing. Upon Subtenant's written request, Sublessor shall present to Landlord, in
the name of Sublessor, any demand requested by Subtenant for any such repairs,
restorations, materials or services required to be furnished to the Sublet
Premises by Landlord. Subtenant shall have the right to exercise, in Sublessor's
name, but at Subtenant's sole cost and expense, all of the rights available to
Sublessor to enforce performance of the obligations of Landlord to make any such
repairs and restorations or to supply any such materials and services to the
demised premises, and no cessation, interruption or suspension of any service
provided by Landlord shall entitle Subtenant to any diminution or abatement of
fixed or additional rent or other compensation under this Sublease, nor shall
this Sublease be affected by reason of any such failure, cessation, interruption
or suspension. Notwithstanding anything contained herein the Sublease shall not
be deemed to grant Subtenant any rights under the Prime Lease which Sublessor
does not have under the Prime Lease, and any act of Sublessor or any 


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omission to act required by the Prime Lease shall in no event be deemed a
violation of this Sublease merely because such act or omission is a violation of
the Prime Lease.

         11. Insurance. Subtenant shall furnish to Sublessor on or before the
Commencement Date of this Sublease evidence that the insurance required to be
obtained pursuant to the Prime Lease has been obtained and as to all such
insurance (i) Subtenant shall cause Sublessor to be named as an additional
insured; (ii) the general liability policy required to be obtained shall also
provide contractual indemnity coverage with respect to the obligations of tenant
under the Prime Lease, (iii) duplicate originals of policies or certificates
required to be delivered to Landlord shall be delivered to Sublessor as well,
and (iv) Subtenant shall deliver to Sublessor a certificate or certificates
containing an endorsement that such insurance shall not be canceled except upon
ten days' prior notice to Landlord and Sublessor.

         12. Assignment Subletting. Subtenant shall not, without the prior
written consents of both Landlord and Sublessor in each instance, by operation
of law or otherwise, assign, mortgage, pledge, sub-sublet, encumber or otherwise
transfer this Sublease (collectively a "Transfer"), nor the estate and term
hereby granted, nor sublet or permit the Sublet Premises or any part thereof to
be used by others. Notwithstanding anything contained above, Sublessor may
withhold such consent in its sole and absolute discretion to any sub-sublet,
assignment or any other Transfer of this Sublease. Notwithstanding anything to
the contrary, affiliated entities controlling, controlled by, or under common
control with, the Subtenant shall not be deemed assignees or Subtenants by
Sublessor. Sublessor shall be listed on the building directory, and Subtenant
shall submit the names of affiliated entities directly to the Landlord for
listing on the building directory.

         13. Repairs, Alterations, Improvements and Other Work:

             (a) After completion of the Build-out, Subtenant shall at no time
make any alterations or improvements to the Sublet Premises without the prior
written consent of both Landlord and Sublessor, which in the case of Sublessor
shall not be unreasonably witheld or delayed. Subtenant shall bear all risk,
liability and expense and in all respects meet the requirements of the Prime
Lease in connection with any alteration whether before, during or after the
build-out. Landlord's consent under the terms of the Prime Lease is a condition
precedent to the making of any alterations or improvements to the extent
required under the Prime Lease.

             (b) Neither Sublessor nor Subtenant shall be required to restore
Subtenant's space on the expiration or earlier termination of the Prime Lease or
the Sublease. Neither Sublessor nor Subtenant shall be required to pay Landlord
or its affiliates any fee for general contracting or related services set forth
in the Prime Lease unless mutually agreed pursuant to a separate agreement.

         14. Time Periods. The time limits provided in the Prime Lease for any
grace periods, for the giving of notices, the making of demands, the performance
of any act, condition or covenant, or the exercise of any right, remedy or
option are changed for the purposes of this Sublease by shortening the same by
three (3) days in each 


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instance, but in the event there shall be remaining less than three (3) days
after giving effect to such shortened term, then the term shall be coextensive
with the time limit provided under the Prime Lease.

         15. Non-Liability, Indemnity. Subtenant shall indemnify and hold
harmless Sublessor, its agents, contractors, servants, licensees, employees or
invitees from and against any and all claims, losses, liabilities, damages,
costs and expenses (including, without limitation, reasonable attorney's fees
and disbursements) arising from (i) the use, conduct or maintenance of the
Sublet Premises or any business therein or any work or thing whatsoever done, or
any condition created in or about the Sublet Premises during the term of this
Sublease (or any time prior to the Commencement Date that Subtenant may have
been given access to the demised premises), (ii) any negligent or otherwise
wrongful act or omission of Subtenant or any of its agents, contractors,
servants, licensees, employees or invitees, and (iii) any failure of Subtenant
to perform or comply with all of the provisions of this Sublease hereof that are
applicable to Subtenant. In case any action or proceeding be brought against
Sublessor or any agent, contractor, servant, licensee, employee or invitee of
Sublessor by reason of any of the foregoing, Subtenant, upon notice from
Sublessor, shall defend such action or proceeding by counsel chosen by
Subtenant, who shall be reasonably satisfactory to Sublessor. Subtenant or its
counsel shall keep Sublessor fully apprised at all times of the status of such
defense and shall not settle same without the written consent of Sublessor.

         16. Destruction by Fire or Other Casualty, Condemnation. If the Sublet
Premises or the Building shall be partially or totally damaged or destroyed by
fire or other casualty, Subtenant shall be entitled to exercise the right to
terminate this Sublease on behalf of Sublessor, pursuant to the provisions of
the Prime Lease.

             (a) If the Sublet Premises are partially or totally damaged by fire
or other casualty as a consequence of which Sublessor shall receive an abatement
of rent and/or additional rent relating to the demised premises, then in such
event, there shall be a pro rata abatement of the fixed rent payable hereunder.

             (b) Subtenant shall give Sublessor and Landlord notice of any fire,
casualty or accident in or about the demised premises promptly after Subtenant
becomes aware of such event.

             (c) If the Prime Lease is terminated pursuant to the provisions
thereof as the result of a taking of all or any portion of the Building by
condemnation (or deed in lieu thereof), this Sublease shall likewise terminate.
In such event, Subtenant shall have no claim to any portion of the award with
respect to any such taking, except to file a claim for the value of its
fixtures, furnishings, or for moving expenses, provided, however, that
Sublessor's award is not thereby reduced or otherwise adversely affected.

         17. Successors and Assigns. Subject to the restrictions on assignment
and subletting in this Sublease and the Prime Lease, this Sublease and the
covenants and agreements herein contained and incorporated herein by reference
shall bind and inure to the benefit of the respective successors and assigns of
the parties.

         18. Entire Agreement; Amendments; Waiver. This Sublease sets forth the
entire agreement of the parties, and shall not be modified or amended except by
a writing signed by the party against whom enforcement is 


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sought. Neither the waiver of any breach by either party of any provisions of
this Sublease, nor any indulgence by either party in respect of any payment due
it hereunder shall be construed as a waiver of any subsequent breach or imply
any future indulgence.

         19. Costs and Expenses. Subtenant shall reimburse Sublessor, on demand,
for all costs and expenses (including attorneys' fees and disbursements and
court costs) incurred by Sublessor in connection with enforcing Subtenant's
obligations under this Sublease, whether incurred in connection with an action
or proceeding commenced by Sublessor or by Subtenant. All such amounts shall be
deemed to be additional rent, and shall be collectible whether incurred before
or after the expiration or termination of this Sublease.

         20. End of Term. Upon the expiration or other termination of this
Sublease, Subtenant shall quit and surrender to Sublessor the Sublet Premises
broom clean in accordance of the Prime Lease, in good order, ordinary wear
excepted, and Subtenant shall remove all of its property therefrom. Should
Sublessor be subject to any fine, cost or expense pursuant to the Prime Lease
because of any holdover or other failure to comply with end of term provisions
by Subtenant, Subtenant will pay as liquidated damages to Sublessor an amount
equal to two and one half (2-1/2) times the amount of such fine, cost or
expense.

         21. Defaults. If Subtenant (a) defaults in the timely payment of any
rent or other charges due Sublessor; (b) if the Sublet Premises are vacated or
deserted by Subtenant; (c) if any execution or attachment shall be issued
against Subtenant or any Subtenant's property whereupon the Sublet Premises
shall be taken or occupied by someone other than Subtenant; (d) if Subtenant
shall fail to move into or take possession of the Sublet Premises within thirty
days after the Commencement Date; or (e) Subtenant defaults in fulfilling any
other covenant under this Sublease not cured within ten (10) days after notice;
then Sublessor may serve a written three days' notice of cancellation of this
Sublease upon Subtenant and upon the expiration of said three days, this
Sublease and the term thereof shall end and expire and Subtenant shall then quit
and surrender the Sublet Premises to Sublessor. This Sublease and the term
thereof shall end and expire and in such event Sublessor may, without notice,
re-enter the Sublet Premises either by force or otherwise, and dispossess
Subtenant by summary proceedings or otherwise, and the legal representative of
Subtenant or other occupant of the Sublet Premises and remove their effects and
hold the Sublet Premises as if this Sublease had not been made, and Subtenant
hereby waives the service of notice of intention to re-enter or to institute
legal proceedings to that end.

         22. Construction. This Sublease shall be governed by and construed
under the law of the State of New York.

         23. Notices. All notices under this Sublease shall be in writing and
shall be deemed to have been sufficiently given when (i) delivered personally,
(ii) sent by postage prepaid certified mail, return receipt requested (air mail
if international), (iii) sent by telex, telegraph, or facsimile transmission, or
(iv) sent by private courier service guaranteeing overnight or three-day
delivery, addressed at the addresses included on Page 1 hereof, or to such other
address as any party may subsequently designate by this notice procedure. Notice
will be deemed 


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effective (i) upon delivery, if delivered personally to the notice address of
either party; or (ii) three (3) business days after mailing, if by certified
mail (air mail if international); and (iii) three business days after deposit
with the courier if sent by courier service with delivery or attempted delivery
confirmed by the courier in writing.

         24. Landlord's Consent. This Sublease shall not become effective, nor
shall the term commence, unless and until the written consent of Landlord to
this Sublease, the build-out plans and the subletting hereunder is obtained.
Subtenant agrees to supply such information and fees as Landlord shall require
in connection with its determination. Sublessor shall promptly request such
consent and furnish Subtenant with a copy thereof when it is obtained. In the
event such written consent of Landlord is not given within sixty (60) days
hereafter, either party may terminate this agreement on five (5) days' written
notice except that if such consent is given within said five-day period, said
notice shall be deemed withdrawn. Both parties shall modify this Sublease to the
extent reasonably required by Landlord.

         IN WITNESS WHEREOF, Sublessor and Subtenant have respectively signed
this Sublease as of the day and year first above written.

                                         ADVANCED HEALTH CORPORATION (Sublessor)


                                         By:(ORIGINAL SIGNATURE)               
                                            ------------------------------------


                                         WESTCO ASSOCIATES, INC., (Subtenant)


                                         By: (ORIGINAL SIGNATURE)              
                                            ------------------------------------


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DENNIS NOSKIN ARCHITECT, P.C.
Architecture/Interior Design/Planning
32 Elm Place
Rye, New York 10580




Floor Plan Design (#22981, Pg 13 of original source)


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DENNIS NOSKIN ARCHITECT, P.C.
Architecture/Interior Design/Planning
32 Elm Place
Rye, New York 10580




Floor Plan Design (#22981, Pg 14 of original source)






                               RECKSON ASSOCIATES
                               555 WHITE PLAINS RD
                               TARRYTOWN, NEW YORK



Job Title : WESTCO                           Job No. 98xxx

Dwg Title: EXISTING CONDITIONS               Scale: 1/32" x 1'-0"

                                             Issue date: 10 FAB 99


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