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                                    Exhibit A

                           KOLL BUSINESS CENTER LEASE

1.       BASIC LEASE TERMS

         a.       DATE OF LEASE EXECUTION: May 16, 1996

         b.       TENANT: Telecommunications Associates Group, Inc., An Ohio 
                  Corporation 
                  Trade Name: Emergency Response Center
                  Address (Leased Premises): 6448 Hwy. 290 East  Building/Unit:
                  E-100 Austin, Texas 78723

         c.       LANDLORD: TR BRELL AUSTIN CORP., An Illinois Corporation,
                  d.b.a.: La Costa Corporation 
                  Address (For Notices): Park, by
                  Koll Management Services, Owner's Authorized Representative
                  located at 6448 Highway 290 East, Suite B-110, Austin, Texas
                  78723 
                  with a copy to Asset Management Division. The Koll
                  Company, P.O. Box 1980, Newport Beach, CA 92660, or to such
                  other place as Landlord may from time to time designate by
                  notice to tenant.

         d.       TENANT'S ONLY PERMITTED USE OF PREMISES: Administration & 
                  Security Alarm Monitoring Offices

         e.       PREMISES AREA: 2,838 Rentable Square Feet

         f.       PROJECT AREA: 100,111 Square Feet

                  Unless otherwise indicated herein, any statement of square
                  footage, rentable or otherwise, set forth in this Lease, or
                  which may have been used in calculating rental or any other
                  amount due under the lease, is an approximation which Landlord
                  and Tenant agree is reasonable, and the rental or any other
                  calculation based upon square footage is not subject to
                  revision whether or not the actual square footage is more or
                  less.

         g.       PREMISES PERCENT OF PROJECT:

         h.       TERM OF LEASE: Commencement June 10, 1996 
                                              Expiration July 31, 1999
                  
                                            Number of Months  37 months, 22 days

         i.       BASED MONTHLY RENT: $ -0-

         j.       RENT ADJUSTMENT (Initial One):

                  (2)   Step Increase. If this provision is initialed, the step
                        adjustment provisions of Section 4.b(2) apply as
                        follows:

<TABLE>
<CAPTION>
                               Effective Date of                 New Base
                                 Rent Increase                 Monthly Rent

                           <S>                                 <C>        
                              July 10,           , 1996        $  2,412.30
                           ----------------------               ----------
                              July 1,            , 1997        $  2,554.20
                           ----------------------               ----------
                              July 1,            , 1998        $  2,554.20
                           ----------------------               ----------
</TABLE>

k.       EXPENSE BASE:
         Expense Stop                      N/A
             or
         Base Year - TAXES & INSURANCE    1996
         
l.       PREPAID RENT:                 $   N/A
         
m.       TOTAL SECURITY DEPOSIT:       $ 2,500.000, including a $ -0-  non-
                                       refundable cleaning fee.
                                                             
n.       BROKER(S): Diana Barbour of Oxford Commercial, Inc.

o.       GUARANTORS:
                        N/A

p.       ADDITIONAL SECTIONS
         Additional sections of this lease numbered 33 through 34 are attached 
         hereto and made a part hereof.  If none, so state in the following 
         space ______________.


q.       ADDITIONAL EXHIBITS
         Additional exhibits lettered A through D are attached hereto
         and made a part hereof. If none, so state in the following
         space ______________.



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2.       PREMISES: Landlord lease to Tenant the premises described in Section 1
         and in Exhibit A (the "Premises"), located in this project described on
         Exhibit B (the "Project"). Landlord reserves the right to modify
         Tenant's percentage of the Project as set forth in Section 1 if the
         Project size is increased through the development of additional
         property. By entry on the Premises, Tenant acknowledges that it has
         examined the Premises and accepts the Premises in their present
         condition, subject to any additional work Landlord has agreed to do.

        3.       TERM: The term of this Lease is for the period set forth in
                 Section 1 commencing on the date in Section 1. If
                 Landlord, for any reason, cannot deliver possession of the
                 Premises to Tenant upon commencement of the term, this Lease
                 shall not be void or voidable, nor shall Landlord be liable to
                 Tenant for any loss or damage resulting from such delay. In
                 that event, however, there shall be a rent abatement covering
                 the period between the commencement of the term and the time
                 when Landlord delivers possession to Tenant, and all other
                 terms and conditions of this Lease shall remain in full force
                 and effect provided, however, that if Landlord cannot deliver
                 possession of the Premises to Tenant. ON OR BEFORE JULY 15,
                 1996, THIS LEASE SHALL BE VOIDABLE. THIS LEASE SHALL BE VOID
                 ONLY WITH PAYMENT OF $800 FROM TENANT FOR LIQUIDATED DAMAGES.
                 If a delay in possession is caused by Tenant's failure to
                 perform any obligation in accordance with this Lease, the term
                 shall commence as set forth in Section 1 and there shall be no
                 reduction of rent between the commencement of the term and the
                 time Tenant takes possession.

4.       RENT:

         A.       BASE RENT. Tenant shall pay Landlord monthly base rent in the
                  initial amount of Section 1 which shall be payable monthly in
                  advance on the first day of each and every calendar month
                  ("Base Monthly Rent") provided, however, the first month's
                  rent is due and payable upon execution of this Lease. If the
                  term of this Lease contains any rental abatement period,
                  Tenant hereby agrees that if Tenant breaches the Lease and/or
                  abandons the Premises before the end of the Lease term, or if
                  Tenant's right to possession is terminated by Landlord because
                  of Tenant's breach of the Lease, Landlord shall, at its
                  option, (1) void the rental abatement period; and (2) recover
                  from Tenant, in addition to any damages due Landlord under the
                  terms and conditions of the Lease, rent prorated for the
                  duration of the rental abatement period at a rental rate
                  equivalent to two (2) times the Base Monthly Rent.

                  For purposes of Section 467 of the Internal Revenue Code, the
                  parties to this Lease hereby agree to allocate the stated
                  rents, provided herein, to the periods which correspond to the
                  actual rent payments as provided under the terms and
                  conditions of this agreement.

         B.       RENT ADJUSTMENT.

         C.       STEP INCREASE. If Section 1.j(2) is initialed, Base Monthly
                  Rent shall be increased periodically to the amounts and at the
                  times set forth in Section 1.j(2).

         D.       EXPENSES. The purpose of this Section 4.c is to ensure that
                  Tenant bears a share of all Expenses related to the use,
                  maintenance, ownership, repair or replacement, and insurance
                  of the Project. Accordingly, beginning on the date Tenant
                  takes possession of the Premises, Tenant shall pay to Landlord
                  that portion of Tenant's share of Expenses related to the
                  Project which is in excess of the Annual Expense Base shown in
                  Section 1.

                  1) EXPENSES DEFINED. The term "Expenses" shall mean all
                     costs and expenses of the ownership, opera, and    
                     insurance of the Project, including without limitation,
                     the following costs:


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         (e)      Real Property Taxes including all taxes, assessments (general
                  and special) and other impositions or charges which may be
                  taxed, charged, levied, assessed or imposed upon all or any
                  portion of or in relation to the Project or any portion
                  thereof, any leasehold estate in tie Premises or measured by
                  rent from the Premises, including any increase caused by the
                  transfer, sale or encumbrance of the Project or any portion
                  thereof. "Real Property Taxes" shall also include any form of
                  assessment, levy penalty, charge or tax (other than estate,
                  inheritance, net income or franchise taxes) imposed by any
                  authority having a direct or indirect power to tax or charge,
                  including, without limitation, any city, county, state,
                  federal or any improvement or other district, whether such tax
                  is (1) determined by the area of the Project or the rent or
                  other sums payable under this Lease; (2) upon or with respect
                  to any legal or equitable interest of Landlord in the Project
                  or any part thereof; (3) upon this transaction or any document
                  to which Tenant is a party creating a transfer in any interest
                  in the Project; (4) in lieu of or as a direct substitute in
                  whole or in part of or in addition to any real property taxes
                  on the Project; (5) based on any parking spaces or parking
                  facilities provided in the Project; or (6) in consideration
                  for services, such as police protection, fire protection,
                  street, side walk and roadway maintenance, refuse removal or
                  other services that may be provided by any governmental or
                  quasi-governmental agency from time to time which were
                  formerly provided without charge or with less charge to
                  property owners or occupants.

     2)  ANNUAL ESTIMATE OF EXPENSES. When Tenant takes possession of the
         Premises, Landlord shall estimate Tenant's portion of Expenses for the
         remainder of the calendar year based on the Tenant's portion of the
         Project Area set forth in Section 1. At the commencement of each
         calendar year thereafter, Landlord shall estimate Tenant's portion of
         Expenses for the coming year based on the Tenant's portion of the
         Project Area set forth in Section 1.

     3)  MONTHLY PAYMENT OF EXPENSES. If Tenant's portion of said estimate of
         Expenses shows an increase for the remainder of the calendar year over
         the Annual Expense Base, as set forth in Section 1, Tenant shall pay to
         Landlord, as additional rent, such estimated increase in monthly
         installments of one-twelfth (1/12) beginning on the date Tenant takes
         possession of the Premises. If Tenant's portion of said estimate of
         Expenses shows an increase for subsequent calendar years over the
         Annual Expense Base, as set forth in Section 1 ,Tenant shall pay to
         Landlord as additional rent, such estimated increase in monthly
         installments o, one-twelfth f1/12) beginning on January 1 of the
         forthcoming calendar year, and one-twelfth 11/12) on the first day of
         each succeeding calendar month. As soon as practical following each
         calendar year, Landlord shall prepare an accounting of actual Expenses
         incurred during the prior calendar year and such accounting shall
         reflect Tenant's share of Expenses. If the additional rent paid by
         Tenant under this Section 4.c.3 during the preceding calendar year was
         less than the actual amount of Tenant's share of Expenses, Landlord
         shall so notify Tenant and Tenant shall pay such amount to Landlord
         within 30 days of receipt of such notice. Such amount shall be deemed
         to have accrued during the prior calendar year and shall be due and
         payable from Tenant even though, the term of this Lease has expired or
         this Lease has been terminated prior to Tenant's receipt of this
         notice. Tenant shall have thirty (30) days from receipt of such notice
         to contest the amount due BUT TENANT SHALL PAY ITS SHARE OF THE
         EXPENSES DURING SUCH PROTEST; failure to so notify Landlord shall
         represent final determination of Tenant's share of expenses.
         If Tenant's payments were greater than the actual amount, then such
         overpayment shall be credited by Landlord to all present rent due under
         this Section 4.c.3. TENANT SHALL HAVE THE RIGHT TO A REASONABLE
         INSPECTION OR AUDIT OF THE BOOKS AND RECORDS OF LANDLORD UPON NOTICE
         AND DURING REGULAR BUSINESS HOURS AT TENANT'S SOLE COST.
         





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     4)  RENT WITHOUT OFFSET AND LATE CHARGE. All rent shall be paid by Tenant
         to Landlord monthly in advance on the first day of every calendar
         month, at the address shown in Section 1, or such other place as
         Landlord may designate in writing from time to time. All rent shall be
         paid without prior demand or notice and without any deduction or offset
         whatsoever. All rent shall be paid in lawful currency of the United
         States of America All rent due for any partial month shall be prorated
         at the rate of 1/30th of the total monthly rent per day. Tenant
         acknowledges that late payment by Tenant to Landlord of any rent or
         other sums due under this Lease will cause Landlord to incur costs not
         contemplated by this Lease the exact amount of such costs being
         extremely difficult and impracticable to ascertain. Such costs include,
         without limitation processing and accounting charges and late charges
         that may be imposed on Landlord by the terms of any encumbrance or note
         secured by the Premises. Therefore, if any rent or other sum due from
         Tenant is not received when clue, Tenant shall pay to Landlord an
         additional sum equal to 10% of such overdue payment. Landlord and
         Tenant hereby agree that such late charge represents fair and
         reasonable estimate of the costs that Landlord will incur by reason of
         any such late payment and that the late charge is in addition to any
         and all remedies available to the Landlord and that the assessment
         and/or collection of the late charge shall not be deemed a waiver of
         any other default. Additionally, all such delinquent rent or other
         sums, plus this late charge, shall bear interest at the then maximum
         lawful rate permitted to be charged by Landlord. Any payments of any
         kind returned for insufficient funds will be subject to an additional
         handling charge of $25.00, and thereafter, Landlord may require Tenant
         to pay all future payments of rent or other sums due by money order or
         cashier's check.

5.   PREPAID RENT. Upon the execution of this Lease Tenant shall pay to Landlord
     the prepaid rent set forth in Section 1, and if Tenant is not in default of
     any provisions of this Lease, such prepaid rent shall be applied toward the
     rent due for the last month of the term. Landlord's obligations with
     respect to the prepaid rent are those of a debtor and not of a trustee, and
     Landlord can commingle the prepaid rent with Landlord's general funds.
     Landlord shall not be required to pay Tenant interest on the prepaid rent.
     Landlord shall be entitled to immediately endorse and cash Tenant's prepaid
     rent; however, such endorsement and cashing shall not constitute Landlord's
     acceptance of this lease. In the event Landlord does not accept this Lease,
     Landlord shall return said prepaid rent.

6.   DEPOSIT. Upon execution this Lease, Tenant shall deposit the security
     deposit set forth in Section 1 with Landlord, in part as security for the
     Performance by Tenant of the provisions of this Lease and in part as a
     cleaning fee. If Tenant is in default, Landlord can use the security
     deposit or any portion of it to cure the default or to compensate Landlord
     for any damages sustained by Landlord resulting from Tenant's default. Upon
     demand, Tenant shall immediately pay to Landlord a sum equal to the portion
     of the security deposit expanded or applied by Landlord to maintain the
     security deposit in the amount initially deposited with Landlord. In no
     event will Tenant have the right to apply any part of the security deposit
     to any rent or other sums due under this Lease. If Tenant is not in default
     at the expiration or termination of this Lease, Landlord shall return the
     entire security deposit to Tenant, except for 10% of first month's rent or
     $125, whichever is greater, which Landlord shall retain as a non-refundable
     cleaning fee. Landlord's obligations with respect to the deposit are those
     of a debtor and not of a trustee, and Landlord can commingle the security
     deposit with landlord's general funds. Landlord shall not be required to
     pay Tenant interest on the deposit. Landlord shall be entitled to
     immediately endorse and cash Tenant's prepaid deposit; however, such
     endorsement and cashing shall not constitute Landlord's acceptance of this
     Lease. In the event Landlord does not accept this Lease, landlord shall
     return said prepaid deposit.

7.   USE OF PREMISES AND PROJECT FACILITIES. Tenant shall use the Premises
     solely for the purposes set forth in Section 1 and for no other purpose
     without obtaining the prior written consent of Landlord. Tenant
     acknowledges that neither Landlord nor any agent of Landlord has made any
     representation of warranty with respect to the Premises or with respect to
     the suitability of the Premises or the Project for the conduct of Tenant's
     business, nor has Landlord agreed to undertake any modification alteration
     or improvement to the Premises or the Project, except as provided in
     writing in this Lease. Tenant acknowledges that Landlord may from time to
     time, at its sole discretion, make such modifications, alterations,
     deletions or improvements to the Project as Landlord may deem necessary or
     desirable, without compensation or notice to Tenant but Landlord will use
     its best effort to prevent interruption to Tenant's business.. Tenant shall
     promptly comply with all laws, ordinances, orders and regulations affecting
     the Premises and the Project, including, without limitation, any rules and
     regulations that may be attached to this Lease and to any reasonable
     modifications to these rules and regulations as Landlord may adopt from
     time to time. Tenant shall not do or permit anything to be done in or about
     the Premises or bring or keep anything in the Premises that will in any way
     increase the premiums paid by Landlord on its insurance related to the
     Project or which will in any way increase the premiums for fire or casualty
     insurance carried by other tenants in the Project Tenant will not perform
     any act or carry on any practices that may injure the Premises or the
     Project; that may be a nuisance or menace to other tenants in the Project;
     or that shall in anyway interfere with the quiet enjoyment of such other
     tenants. Tenant shall not use the Premises for sleeping, washing clothes,
     cooking or the preparation, manufacture or mixing of anything that might
     emit any objectionable odor, noise, vibrations or lights onto such other
     tenants. If sound insulation is required to muffle noise produced by Tenant
     on the Premises, Tenant at its own cost shall provide all necessary
     insulation. Tenant shall not do any thing on the Premises which will
     overload any existing parking or service to the Premises. Pets and/or
     animals of any type shall not be kept on the Premises with the exception of
     seeing-eye dogs.

     On trash generated in the normal course of the business of Tenant's
     Permitted Use, and only such trash actually generated by work on site in
     the Leased Premises, may be disposed of in trash containers at the
     designated







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     locations. Only the materials permitted by law to be disposed of in the
     containers may be so disposed of, and under no circumstances may "hazardous
     waste" materials be disposed of in Project trash containers. No trash or
     scrap materials may be brought into the Premises, Project or Property at
     any time for disposal, storage, or any other purpose. No "trade" trash,
     including but not limited to, industrial scrap, carpet scrap, or wallboard
     may be disposed of in the containers. No storing of trash or scrap is
     permitted in or about the Premises, Project or Property. In the event
     Tenant generates more trash by work on site in the Leased Premises in the
     normal course of Tenant's permitted use than can be handled with the
     current pickup, Tenant shall be assessed the costs, and Tenant shall be
     exclusively responsible immediately to pay for upon demand, any additional
     service.

8.   SIGNANGE. All signing shall comply with rules and regulations set forth by
     Landlord as may be modified from time to time. Current rules and
     regulations relating to signs are described on Exhibit C. Tenant shall
     place no window covering (e.g., shades, blinds, curtains, drapes, screens,
     or tinting materials), stickers, signs, lettering, banners or advertising
     or display material on or near exterior windows or doors if such materials
     are visible from the exterior of the Premises, without Landlord's prior
     written consent. Similarly, Tenant may not install any alarm boxes, foil
     protection tape or other security equipment on the Premises without
     Landlord's prior written consent. Any material violating this provision may
     be destr4oyed by Landlord without compensation to Tenant.

9.   PERSONAL PROPERTY TAXES. Tenant shall pay before delinquency all taxes,
     assessments, license fees and public charges levied, assessed or imposed
     upon its business operations as well as upon all trade fixtures, leasehold
     improvements, merchandise and other personal property in or about the
     Premises.

10.  PARKING. Landlord grants to Tenant and Tenant's customers, suppliers,
     employees and invitees, a non-exclusive license to use the designated
     parking areas in the Project for the use of motor vehicles during the term
     of this Lease. Landlord reserves the right at any time to grant similar
     non-exclusive use to other tenants, to promulgate rules and regulations
     relating to the use of such parking areas, including reasonable
     restrictions on parking by tenants and employees, to designate specific
     spaces for the use of any tenant, to make changes in the parking layout
     from time to time, and to establish reasonable time limits on parking.
     Overnight parking is prohibited and any vehicle violating this or any other
     vehicle regulation adopted by Landlord is subject to removal at the owner's
     expense.

11.  UTILITIES. (Strike and initial clause which does not apply).

     A.    OFFICE SPACE. Landlord shall provide, in the area shown on Exhibit A
           hereto as office space, all heat, electricity, air conditioning and
           gas, if any, during the hours of 8:00 a.m. to 6:00 p.m., Monday
           through Friday, except legal holidays and water for restroom
           facilities, if any. If Tenant uses water, electricity, heat or air
           conditioning in excess of normal office use, Landlord may separate
           meter the increased use and Tenant shall pay the increased cost
           directly to the appropriate utility; or Landlord may, in its sole
           judgment, measure or estimate the increase use and Tenant shall pay
           Landlord, on demand, any increased costs so measured or estimated. In
           any event, Tenant shall pay all telephone, waste removal and any
           other services for which Tenant shall contract.

     B.    INDUSTRIAL SPACE. Tenant shall pay for all heat,
           light, power, electricity, telephone or other service
           metered, chargeable or provided to the Premises. Landlord
           reserves the right to install separate meters for any such
           utility and to charge Tenant for the costs of such
           installation.

12.  MAINTENANCE. Landlord shall maintain, in good condition, the structural
     parts of the Premises, which shall include only the foundation, bearing and
     exterior walls (excluding glass), subflooring and roof (excluding
     skylights), the unexposed electrical, plumbing and sewerage systems,
     including without limitation, those portions of the systems lying outside
     the Premises, exterior doors (excluding glass), window frames, gutters and
     downspouts on the Building and the heating, ventilating and air
     conditioning system servicing the Premises; Except as provided above,
     Tenant shall maintain and repair the Premises in good condition,
     including, without limitation, maintaining and repairing all walls,
     floors, ceiling, interior doors, exterior and interior windows and
     fixtures as well as damage caused by Tenant, its agents, employees or
     invitees. Upon expiration or termination of this Lease, Tenant shall
     surrender the Premises to Landlord in the same condition as existed at the
     commencement of the term, except for reasonable wear and tear or damage
     caused by fire or other casualty for which Landlord has received all funds
     necessary for restoration of the Premises from insurance proceeds.

13.  ALTERATIONS. Except Tenant's requirements for telephone lines, cabling and
     equipment, provided in Paragraph 33 and Paragraph 34, Tenant shall not make
     any alterations to the Premises, or to the Project, including any changes
     to the existing landscaping, without Landlord's prior w2riten consent. If
     Landlord gives its consent to such alternations, Landlord may post notices
     in accordance with the laws of the state in which the premises are located.
     Any permanent, non-removable alterations made shall remain on and be
     surrendered with the Premises upon expiration or termination of this Lease,
     except that Landlord may, within 30 days before the 30n days after
     expiration of the term, elect to require Tenant to remove any alterations
     which Tenant may have made to the Premises. If Landlord so elects, at its
     own cost Tenant shall restore the Premises to the condition designated by
     Landlord in its election, before the last day of the term or within 30 days
     after notice of its election is given, whichever is later.

     Should Landlord consent in writing to Tenant's alteration of the Premises,
     Tenant shall contract with a contractor approved by Landlord for the
     construction of such alterations, shall secure all appropriate governmental
     approvals and permits, and shall complete such alterations with due
     diligence in compliance with plans and specifications approved by Landlord.
     All such construction shall be performed in a manner which will not





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     interfere with the quiet enjoyment of other tenants of the Project. Tenant
     shall pay all costs for such construction and shall keep the Premises and
     the Project free and clear of all mechanics' liens which may result from
     construction by Tenant. If Landlord gives its consent, no such alterations
     will proceed without Landlord's prior written approval of Tenant's
     contractor, which shall be conditioned on proof of insurance by Tenant's
     contractor for public liability and automobile liability and property
     damage insurance with limits not less than $1,000,000/$250,000/$500,000
     respectively endorsed to show Landlord as an additional insured and for
     worker's compensation as required and detailed plans and specifications for
     such work.

     Tenant will keep the Premises and Property free from any liens arising out
     of any work performed, materials furnished or obligations incurred by
     Tenant, its agents or contractors. Tenant agrees that should any lien be
     posted on the property due to work performed, materials furnished, or
     obligations incurred by it, that it will immediately notify and proceed to
     remove such lien. Tenant further acknowledges that it will remain liable to
     landlord and indemnify it for any costs or damages to Landlord or the
     property as a result of such liens. Landlord has the right to post and keep
     posted in the Premises and/or Property, any notices that may be provided by
     law or which Landlord may deem to be proper for the protection of Landlord,
     the Premises and/or Property from such liens.

14.  RELEASE AND INDEMNITY. As material consideration to Landlord, Tenant agrees
     that Landlord shall not be liable to Tenant for any damage to Tenant or
     Tenant's property from any cause, and Tenant waives all claims against
     Landlord for damage to persons or property arising from any reason, except
     for damage resulting directly from landlord's breach of its express
     obligations under this Lease which landlord has not cured within a
     reasonable time after receipt of written notice of such breach from Tenant
     or Landlord's, its employees';, representatives', or agents' willful
     misconduct. Tenant shall indemnify and hold Landlord harmless from all
     damages arising out of any damage to any person or property occurring in,
     on or about the Premises or Tenant's use of the Premises or Tenant's breach
     of any term of this Lease.

15.  INSURANCE. Tenant, at its cost, shall maintain public liability and
     property damage insurance and products liability insurance with a single
     combined liability limit of $1,000,000 insuring against all liability of
     Tenant and its authorized representatives arising out of or in connection
     with Tenant's use or occupancy of the Premises. Public liability insurance,
     products liability insurance and property damage insurance shall insure
     performance by Tenant of the indemnity provisions of Section 143. Landlord
     shall be named as additional insured and the policy shall contain
     cross-liability endorsements. On all its personal property, at its cost,
     Tenant shall maintain a policy of standard fire and extended coverage
     insurance with vandalism and malicious mischief endorsements and all risk"
     coverage on ______ Tenant's improvements and alterations in or about the
     Premises, to the extent of at least 90% of their full replacement value.
     The proceeds from any such policy shall be used by Tenant for the
     replacement of personal property and the restoration of Tenant's
     improvements or alterations. This policy will contain an express waiver, in
     favor of Landlord, of any right or subrogation by the insurer. All
     insurance required to be provided by Tenant under this Lease shall release
     Landlord from any claims for damage to any person or the Premises and the
     Project, and to Tenant's fixtures, personal property, improvements and
     alterations in or on the Premises or the Project, caused by or resulting
     from risks insured against under any insurance policy carried by Tenant and
     in force at the time of such damage. All insurance required to be provided
     by Tenant under this Lease: (a) shall be issued by Insurance companies
     authorized to do business in the state in which the premises are located
     with a financial rating of at least an A XII status as related in the most
     recent edition of Best's Insurance Reports; (b) shall be issued as a
     primary policy; and (c) shall contain an endorsement requiring at least 30
     days written notice of cancellation to Landlord and Landlord's lender,
     before cancellation or change in coverage, scope or amount of any policy.
     Tenant shall deliver a certificate or copy of such policy together with
     evidence of payment of all current premiums to Landlord within 30 days of
     execution of this Lease. Tenant's failure to provide evidence of such
     coverage to landlord may, in Landlord's sole discretion, constitute a
     default under this Lease.

16.  DESTRUCTION. If during the term, the Premises or Project are more than 10%
     destroyed from any cause, or rendered inaccessible or unusable from any
     cause, Landlord may, in its sole discretion terminate this Lease by
     delivery of notice to Tenant within 30 days of such event without
     compensation to Tenant. If in Landlord's estimation the Premises cannot be
     restored within 90 days following such desecration, the landlord shall
     immediately notify Tenant and Tenant may terminate this Lease by delivery
     of notice to Landlord within 30 days of receipt of Landlord's notice. If
     landlord does not terminate this lease and if in landlord's estimation the
     Premises can be restored within 90 days, then Landlord shall commence to
     restore the Premises in compliance with then existing laws and shall
     complete such restoration with due diligence. In such event, this Lease
     shall remain in full force and effect, but there shall be an abatement of
     rent between the date of destruction and the date of completion of
     restoration, based on the extent to which destruction interferes with
     Tenant's use of the Premises.

17.  CONDEMNATION.

     a.  OBLIGATIONS TO BE GOVERNED BY LEASE. If during the-term of the Lease
         there is any taking of all or any part of the Premises or the Project,
         the rights and obligations of the parties shall be determined pursuant
         to this Lease.

     b.  TOTAL OR PARTIAL TAKING. If the Premises are totally taken by
         condemnation, this Lease shall terminate on the date of taking. If any
         portion of the Premises is taken by condemnation, this Lease shall
         remain in effect, except that Tenant can elect to terminate this Lease
         if the remaining portion of the Premises is rendered unsuitable for
         Tenant's continued use of the Premises. If Tenant elects to terminate
         this Lease,


                                       6
<PAGE>   7


         Tenant must exercise its right to terminate by giving notice to
         Landlord within 30 days after the nature and extent of the taking have
         been finally determined. If Tenant elects to terminate this Lease,
         Tenant shall also notify Landlord of the date of termination, which
         date shall not be earlier than 30 days nor later than 90 days after
         Tenant has notified Landlord of its election to terminate; except that
         this Lease shall terminate on the date of taking if the date of taking
         falls on a date before the date of termination as designated by Tenant.
         If any portion f the Premises is taken by condemnation and this Lease
         remains in full force and effect, on the date of taking the rent shall
         be reduced by an amount in the same ratio as the total number of square
         feet in the Premises taken bears to the total number of square feet in
         the Premises immediately before the date of taking. Tenant will not
         because of such taking assert any claim against the Landlord or the
         taking authority for any compensation because of such taking, and
         Landlord will be entitled to receive the entire amount of any
         compensation or award without deduction for any estate of interest of
         Tenant, unless Landlord would not be entitled to such award and such
         award or part thereof does not diminish Landlord's award.



18.  ASSIGNMENT OR SUBLEASE. Tenant shall not assign or encumber its interest in
     this Lease or the Premises or sublease all or any part of the Premises or
     allow any other person or entity (except Tenant's authorized
     representatives, employees, invitees, or guests) to occupy or use all or
     any part of the Premises without first obtaining Landlord's consent which
     Landlord may withhold in its sole discretion. Any assignment, encumbrance
     or sublease without Landlord's written consent shall be voidable and at
     Landlord's election, shall constitute a default. If Tenant is a partnership
     a withdrawal or change, voluntary, involuntary or by operation of law of
     any partner; or the dissolution of the partnership, shall be deemed a
     voluntary assignment. If Tenant consists of more than one person, a
     purported assignment, voluntary or involuntary or by operation of law from
     one person or the other shall be deemed a voluntary assignment. If Tenant
     is a corporation, any dissolution, merger; consolidation or other
     reorganization of Tenant, or sale or other transfer of a controlling
     percentage of the capital stock of Tenant, or the sale of at least 25% of
     the value of the assets of Tenant shall be deemed a voluntary assignment.
     The phrase "controlling percentage" means ownership of and right to vote
     stock possessing at least 25% of the total combined voting power of all
     classes of Tenant's capital stock issued, outstanding and entitled to vote
     for election of directors. This Section 18 shall not apply to corporations
     the stock of which is traded through an exchange or over the counter. All
     rent received by Tenant from its subtenants in excess of the rent payable
     by Tenant to Landlord under this Lease shall be paid to Landlord, or any
     sums to be paid by an assignee to Tenant in consideration of the assignment
     of this Lease shall be paid to Landlord. If Tenant requests Landlord to
     consent to a proposed assignment or subletting, Tenant shall pay to
     Landlord, whether or not consent is ultimately given, $100 or Landlord's
     reasonable attorneys' fees incurred in connection with such request,
     whichever is greater. Any transfer of a controlling percentage of capital
     stock to merger, consolidation or reorganization with any affiliated
     entity, family member or person having interest in Tenant shall not be
     deemed an assignment or subletting hereunder.
     

     No interest of Tenant in this Lease shall be assignable by involuntary
     assignment through operation of law (including without limitation the
     transfer of this Lease by testacy or intestacy). Each of the following acts
     shall be considered an involuntary assignment: (a) If Tenant is or becomes
     bankruptcy or insolvent, makes an assignment for the benefit of creditors,
     or institutes proceedings under the Bankruptcy Act in which Tenant is the
     bankrupt; or if Tenant is a partnership or consists of more than one person
     or entity, if any partner or the partnership or other person or entity is
     or becomes bankrupt or insolvent or makes an assignment for the benefit of
     creditors; or (b) ____ a writ of attachment or execution ________ on this
     Lease; or (c) If in any proceeding or action ____ which Tenant is a party,
     a receiver is appointed with authority to take possession of the Premises.
     An involuntary assignment shall constitute a default by Tenant and Landlord
     shall have the right to elect to terminate this Lease, in which case the
     Lease shall not be treated as an asset of Tenant.

19.  DEFAULT. The occurrence of any of the following shall constitute a default
     by Tenant. (a) A failure to pay rent or other charge when due and such
     default continues for a period of 5 (five) days after such written notice
     of default occurs: (b) Abandonment and vacation of the Premises (failure to
     occupy and operate the Premises for ten consecutive days shall be deemed an
     abandonment and vacation); or (c) Failure to perform any other provision of
     this Lease and such default continues for 15 (fifteen) days after such
     written notice of default occurs.

20.  LANDLORD'S REMEDIES. Landlord shall have the following remedies if Tenant
     is in default. (These remedies are not exclusive; they are cumulative and
     in addition to any remedies now or later allowed by law): Landlord may
     terminate Tenant's right to possession of the Premises at any time. Tenant
     hereby grants Landlord full and free right, whether by changing or picking
     of locks in necessary, to enter and repossess the Premises, with or without
     process of law. Tenant releases Landlord of any liability for any damage
     resulting therefrom and waives any right to claim damage for such re-entry.
     Tenant also agrees that Landlord has not waived or relinquished any other
     right given to it hereunder or by operation of law. No act by Landlord
     other than giving notice to Tenant shall terminate this Lease. Acts of
     maintenance, efforts to relet the Premises, or the appointment of a
     receiver on Landlord's initiative to protect Landlord's interest under this
     Lease shall not constitute a termination of Tenant's right to possession.
     Upon termination of Tenant's right to possession, Landlord has the right to
     recover from Tenant: (1) The worth of the unpaid rent that had been earned
     at the time of termination of Tenant's right to possession; (2) The worth
     of the amount of the unpaid rent that would have been earned after the date
     of termination of Tenant's right to possession; (3) Any other amount,
     including court, attorney and collection costs necessary to compensate
     Landlord for all detriment proximately caused by Tenant's default. "The
     Worth," as used for Item 20(1) in this Paragraph 20 is to be computed by
     allowing interest at the maximum rate an individual is permitted to charge
     by law or 12%, whichever is greater. "The worth at the time of the





                                       7

<PAGE>   8


     award" as used for Item 20(2) in this Paragraph 20 is to be computed by    
     discounting the amount at the discount rate of the Federal Reserve Bank of
     San Francisco at the time of termination of Tenant's right of possession.

21.  ENTRY ON PREMISES. Landlord and its authorized representatives shall have
     the right to enter the Premises at all reasonable times for any of the
     following purposes: (a) To determine whether the Premises are in good
     condition and whether Tenant is complying with its obligations under this
     Lease; (b) To do any necessary maintenance and to make any restoration to
     the Premises or the Project that Landlord has the right or obligation to
     perform; (c) To post "for sale" signs at any time during the term, to post
     "for rent" or "for lease" signs during the last 90 days of the term, or
     during any period while Tenant is in default; (d) To show the Premises to
     prospective brokers, agents, buyers, tenants or persons interested in
     leasing or purchasing the Premises, at any time during the term; or (e) To
     repair, maintain or improve the Project and to erect scaffolding and
     protective barricades around and about the Premises but not so as to
     prevent entry to the Premises and to do any other act or thing necessary
     for the safety or preservation of the Premises or the Project. Landlord
     shall not be liable in any manner for any inconvenience, disturbance, loss
     of business, nuisance or other damage arising out of Landlord's entry onto
     the Premises as provided in this Section 21. Tenant shall not be entitled
     to an abatement or reduction of rent if Landlord exercises any rights
     reserved in this Section 21. Landlord shall conduct his activities on the
     Premises as provided herein in a manner that will cause the least
     inconvenience, annoyance or disturbance to Tenant. For each of these
     purposes, Landlord shall at all times have and retain a key with which to
     unlock all the doors in, upon and about the Premises, excluding Tenant's
     vaults and sales. Tenant shall not alter any lock or install a new or
     additional lock or bolt on any door of the Premises without prior written
     consent of Landlord. If Landlord gives its consent, Tenant shall furnish
     Landlord with a key for any such lock.

22.  SUBORDINATION. Without the necessity of any additional document being
     executed by Tenant for the purpose of effecting a subordination, and at the
     election of Landlord or any mortgagee or any beneficiary of a Deed of Trust
     with a lien on the Project or any ground lessor with respect to the
     Project, this Lease shall be subject and subordinate at all times to (a)
     all ground leases or underlying leases which may now exist or hereafter be
     executed affecting the "Project, and (b) the lien of any mortgage or deed
     of trust which may now exist or hereafter be executed in any amount for
     which the Project, ground leases or underlying leases, or Landlord's
     interest or estate in any of said items is specified as security. In the
     event that any ground lease or underlying lease terminates for any reason
     or any mortgage or Deed of Trust is foreclosed or a conveyance in lieu of
     foreclosure is made for any reason, Tenant shall, notwithstanding any
     subordination, attorn to the become the Tenant of the successor in interest
     to Landlord, at the option of such successor in interest. Tenant covenants
     and agrees to execute and deliver; upon demand by Landlord and in the form
     requested by Landlord any additional documents evidencing the priority or
     subordination of this Lease with respect to any such ground lease or
     underlying leases or the lien of any such mortgage or Deed of Trust. Tenant
     hereby irrevocably appoints Landlord as attorney-in-fact of Tenant to
     execute, deliver and record any such document in the name and on behalf of
     Tenant.

     Tenant, within ten days from notice from Landlord, shall execute and
     deliver to Landlord, in recordable form, certificates stating that this
     Lease is not in default, is unmodified and in full force and effect, or in
     full force and effect as modified, and stating the modification. This
     certificate should also state the amount of current monthly rent, the dates
     to which rent has been paid in advance, and the amount of any security
     deposit and prepaid rent. Failure to deliver this certificate to Landlord
     within ten days shall be conclusive upon Tenant that this Lease is in full
     force and effect and has not been modified except as may be represented by
     Landlord.

23.  NOTICE. Any notice, demand, request, consent, approval or communication
     desired by either party or required to be given, shall be in writing and
     served either personally or sent by prepaid certified first class mail,
     addressed as set forth in Section 1. Either party may change its address by
     notification to the other party. Notice shall be deemed to be communicated
     48 hours from the time of mailing, or from the time of service as provided
     in this Section 23.

24.  WAIVER. No delay or omission or remedy by Landlord shall impair such right
     or remedy by Landlord shall impair such right or remedy or be construed as
     a waiver. No act or conduct of Landlord, including without limitation,
     acceptance of the keys to the Premises, shall constitute an acceptance of
     the surrender of the Premises by Tenant before the expiration of the term.
     Only written notice from Landlord to Tenant shall constitute acceptance of
     the surrender of the Premises and accomplish termination of the Lease.
     Landlord's consent to or approval of any act by Tenant requiring Landlord's
     consent or approved shall not be deemed to waive or render unnecessary
     Landlord's consent to or approval of any subsequent act by Tenant. Any
     waiver by Landlord of any default must be in writing and shall not be a
     waiver of any other default concerning the same or any other provision of
     the Leases.

25.  SURRENDER OF PREMISES: Upon expiration of the term, Tenant shall surrender
     to Landlord the Premises and all Tenant improvements and alterations in
     good condition, except for ordinary wear and tear and alterations Tenant
     has the right or is obligated to remove under the provisions of Section 13
     herein. Tenant shall remove all personal property including, without
     limitation, all wallpaper; paneling and other decorative improvements or
     fixtures and shall perform all restoration made necessary by the removal of
     any alterations or Tenant's personal property before the expiration of the
     term, including for example, restoring all wall surfaces to their condition
     prior to the commencement of this Lease. Landlord can elect to retain or
     dispose of in any manner Tenant's personal property not removed from the
     Premises by Tenant prior to the expiration of the term. Tenant waives all
     claims against Landlord for any damage to Tenant resulting from Landlord's
     retention or disposition of Tenant's





                                       8
<PAGE>   9


     personal property. Tenant shall be liable to Landlord's costs for storage,
     removal or disposal of Tenant's personal property.

     If Tenant, with Landlord's consent, remains in possession of the Premises
     after expiration or termination of the term, or after the date in any
     notice given by Landlord to Tenant terminating this Lease, such possession
     by Tenant shall be deemed to be a month-to-month tenancy terminable on
     written 30-day notice at any time, by either party. All provisions of this
     Lease, except those pertaining to term and rent, shall apply to the
     month-to-month tenancy. Tenant shall pay monthly rent in an amount equal to
     125% of Rent for the last full calendar month during the regular term plus
     100% of said last month's estimate of Tenant's share of Expenses pursuant
     to Section 4.c43.

26.  LANDLORD'S LIEN/STORAGE. As security for payment of rent, damages and all
     other payments required to be made by this Lease, Tenant hereby grants to
     Landlord a lien upon all property of Tenant now or subsequently located
     upon the leased Premises. If Tenant abandons or vacates any substantial
     portion of the Lease Premises or is in default in the payment of any rent
     or additional rent, damages or other payments required to be made by this
     Lease or is in default of any other provision of this Lease, Landlord may
     enter upon the leased premises, whether by changing or picking locks, and
     take possession pursuant to this Lease of all or any part of the personal
     property, and may sell all or any part of the personal property at a public
     or private sale, in one or successive sales to the highest bidder all of
     Tenant's title and interest in the personal property sold to him.

     Any and all property which may be removed from the Premises by Landlord
     pursuant to the authority of this Lease or of law, to which Tenant is or
     may be entitled, may be handled, removed and stored, as the case may be, by
     or at the direction of Landlord at the risk, cost and expanse of Tenant,
     and Landlord shall in no event be responsible for the value, preservations
     or safekeeping thereof. Tenant shall pay to Landlord, upon demand, any and
     all expenses incurred in such removal and all storage charges against such
     property so long as the same shall be in Landlord's possession or under
     Landlord's control. Any such property of Tenant not retaken by Tenant from
     storage within 30 days after removal from the Premises shall, at Landlord's
     option, be deemed conveyed by Tenant to Landlord under this Lease as by a
     bill of sale without further payment or credit by Landlord to Tenant.

27.  RULES AND REGULATIONS. Tenant will faithfully observe and comply with the
     Rules and Regulations printed on or attached to this Lease and Landlord
     reserves the right to modify and amend them as it deems necessary. Landlord
     will not be responsible to Tenant for the nonperformance by any other
     lessee or occupant of the Project of any of said Rules and Regulations.

     Violation of any such Rules and Regulations shall be deemed a material
     breach of this Lease by Tenant.

28.  PROJECT PLAN. In the event Labor requires the Premises for use in
     conjunction with another suite or for other reasons connected with the
     Project planning program, Landlord, upon notifying Tenant in writing, shall
     have the right to move Tenant to space in the Project of which the Premises
     forms a part, at Landlord's sole cost and expense , and the terms and      
     conditions of the original Lease will remain in full force and effect
     excepting that the Premises will now be in a new location. However, i the
     new space does not meet with Tenant's approval, Tenant will have the right
     to cancel this Lease upon giving Landlord thirty (30) days' notice within
     ten (10) days of receipt of Landlord's notification. Should Tenant elect
     to cancel the Lease as provided in this paragraph, the effective
     expiration date will equal the projected move-in date of the suit3
     Landlord wishes Tenant to move to as indicated in Landlord's written
     notification to Tenant.

29.  FORCE MAJEURE. Landlord will have no liability to Tenant, nor will Tenant
     have any right to terminate this Lease or abate Monthly Rent or Additional
     Rent or assert a claim of partial or total actual or constructive eviction,
     because of Landlord's failure to perform any of its obligations in the
     Lease if the failure is due in part or in full to reasons beyond Landlord's
     reasonable control, including without limitation, strikes, or other labor
     difficulties, inability to obtain necessary governmental permits and
     approvals, war, riot, mandatory or prohibitive injunction issued in
     connection with the civil insurrection, accidents, acts of God, and
     governmental preemption in connection with a national emergency
     (collectively referred to as "Force Majeure"). If Landlord fails to perform
     its obligations because of any reasons beyond Landlord's reasonable control
     (including those enumerated above), the period for Tenant's performance
     will be extended day for day for the duration of the cause of Landlord's
     failure, except for Tenant's obligation to pay Rent as required under the
     Lease.

30.  SECURITY MEASURES. Tenant hereby acknowledges that the rental payable to
     Landlord hereunder does not include the cost of guard service or other
     security measures, and that Landlord shall have no obligation whatsoever to
     provide same. Tenant assumes all responsibility for the protection of the
     Premises, and all real and personal property that it, its agents,
     and/or its invitees may use, from the acts of third parties.

31.  PERFORMANCE UNDER PROTEST. If at any time a dispute shall arise as to any
     amount or sum of money to be paid by one part to the other under the
     provisions hereof, the party against whom the obligation to pay the money
     is asserted shall have the right to make payment "under protest" and such
     payment shall not be regarded as a voluntary payment and shall survive the
     right on the part of said party to initiate suit or other action for
     recovery of such sum. If it shall be adjudged that there was no legal
     obligation on the part of said party to pay such sum or any part thereof,
     said party shall be entitled to recover such sum or so much thereof as it
     was not legally required to pay under the provisions of this Lease.




                                       9
<PAGE>   10




32.  LIMITATION OF LIABILITY. In consideration of the benefits accruing
     hereunder, Tenant agrees that, in the event of any actual or alleged
     failure, breach or default of this Lease by Landlord, if Landlord is a
     partnership:

     a.    The sole and exclusive remedy shall be against the partnership and
           its partnership assets;

     b.    No partner of Landlord shall be sued or named as a party in any suit
           or action (except as may be necessary to secure jurisdiction of the
           partnership;

     c.    No service of process shall be made against any partner of Landlord
           (except as may be necessary to secure jurisdiction of the
           partnership);

     d.    No partner of Landlord shall be required to answer or otherwise plead
           to any service or process;

     e.    No judgment may be taken against any partner of Landlord;

     f.    Any judgment taken against any partner of Landlord may be vacated and
           set aside at any time without hearing;

     g.    No writ of execution will ever be levied against the assets of any
           partner of Landlord; and

     h.    These covenants and agreements are enforceable both by Landlord and
           also by any partner of Landlord.

           Tenant agrees that each of the foregoing provisions shall be
           applicable to any covenant or agreement either expressly contained in
           this Lease or imposed by statute or at common law.

33.  MISCELLANEOUS PROVISIONS.

     a.    TIME OF ESSENCE. Time is of the essence of each provision of this
           Lease.

     b.    SUCCESSOR. This Lease shall be binding on and inure to the benefit of
           the parties and their successors, except as provided in Section 18
           herein.

     c.    LANDLORD'S CONSENT. Any consent required by Landlord under this Lease
           must be granted in writing and may be withheld by Landlord in its
           sole and absolute discretion.

     d.    COMMISSIONS. Each party represents that it has not had dealings with
           any real estate broker, finder or other person with respect to this
           Lease in any manner, except for the broker identified in Section 1,
           who shall be compensated by Landlord.

     e.    OTHER CHARGES. If Landlord becomes a party to any litigation
           concerning this Lease, the Premises or the Project, by reason of any
           act or omission of Tenant or Tenant's authorized representatives,
           Tenant shall be liable to Landlord for reasonable attorneys' fees and
           court costs incurred by Landlord in the litigation whether or not
           such litigation leads to actual court action. Should the court render
           a decision which is thereafter appealed by any party thereto, Tenant
           shall be liable to Landlord for reasonable attorneys' fees and court
           costs incurred by Landlord in connection with such appeal.

           If either party commences any litigation against the other party or
           files an appeal of a decision arising out of or in connection with
           the Lease, the prevailing party shall be entitled to recover from the
           other party reasonable attorneys' fees and costs of suit. If Landlord
           employs a collection agency to recover delinquent charges, Tenant
           agrees to pay all collection agency and attorneys' fees charges to
           Landlord in addition to rent, late charges, interest and other sums
           payable under this Lease. Tenant shall pay a charge of $75 to
           Landlord for preparation of a demand for delinquent rent.

     f.    AUTHORITY. If either party hereto is a corporation, trust or general
           or limited partnership, each individual executing this Lease on
           behalf of such entity represents and warrants that he or she is duly
           authorized to execute and deliver this Lease on its behalf. If Tenant
           is a corporation, trust or partnership, Tenant shall, within thirty
           (30) days after request by Landlord, deliver to Landlord evidence
           satisfactory to Landlord of such authority.

     g.    OFFER. Any preparation of this document by Landlord or Landlord's
           agent and submission of same to Tenant shall not be deemed to be a
           proposal, offer or contract to lease to Tenant. This document cannot
           be unilaterally accepted by Tenant and thereby made binding upon
           Landlord. This document is not binding on any party and has no force
           or effect until executed by all parties hereto.

     h.    LANDLORD'S SUCCESSORS. In the event of a sale or conveyance by
           Landlord of the Project, the same shall operate to release Landlord
           from any liability under this Lease, and in such event Landlord's
           successor in interest shall be solely responsible for all obligations
           of Landlord under this Lease.

     i.    INTERPRETATION. This Lease shall be construed and interpreted in
           accordance with the laws of the state in which the premises are
           located. This lease constitute the entire agreement between the
           parties with respect to the Premises and the Project, except for such
           guarantees or modifications as may be executed in writing by the
           parties from time to time. When required by the context of this
           Lease, the singular shall include the plural, and the masculine shall
           include the feminine and/or neuter. "Party" shall mean Landlord or
           Tenant. If more than one person or entity constitutes Landlord or
           Tenant, the obligations



                                      10
<PAGE>   11




           imposed upon that party shalal be joint and several. The
           enforceability, invalidity or illegality of any provision shall not
           render the other provisions unenforceable, invalid or illegal.



<TABLE>
<CAPTION>
LANDLORD:                                               TENANT:

<S>                                                     <C>    
TR BRELL AUSTIN CORP., c/o                              Telecommunications Associates Group, Inc., an Ohio
Koll Management Services, Owner's Authorized            corporation, d/b/a Emergency Response Center
representatives, Koll Management Services, on
behalf of Owner, d/b/a La Costa Corporate Park



By:_____________________________________                By:________________________________________
Title:__________________________________                Title:_____________________________________

Date:______________________                             Date:______________________

</TABLE>



                                      11

<PAGE>   12


ADDITIONAL SECTIONS:

33.0 EMERGENCY GENERATOR. Landlord herein grants to Tenant, subject to the terms
and conditions below, permission to install at the rear of suites E-101 and
E-102 an emergency generator. Tenant agrees that said emergency generator will:

     (1)   Take up no more than 48 square feet;

     (2)   Weigh, including supports, stands and attachments, no more than 500
           pounds;

     (3)   Be mounted on sleepers or sleds so as to be moveable; and

     (4)   Neither the generator nor other apparatus can be visible from the
           street.

Tenant agrees that its liability insurance policy will be amended to cover any
and all damage whether by acts of God, negligence or otherwise, caused directly
or indirectly by the emergency generator, its stands, supports, etc. Failure of
Tenant to provide proof of such amended coverage shall give Landlord the
unqualified right to remove the generator with no liability on Landlord's part
regardless of any damage thereof.

Tenant agrees that it will indemnify and hold harmless Landlord from any damage
caused by the generator or its use.

Upon removal of the generator, whether by termination of the Lease or by demand
of Landlord, Tenant agrees that it will be responsible for returning the
Premises and all penetrations to the building by virtue of such use or
installation of the generator to its original condition at it sole cost to
Landlord's sole satisfaction.

34.0 TELEPHONE LINES. Landlord herein grants to Tenant the right to use 20
existing telephone lines during the term of this Lease. If it becomes necessary
for Tenant to expand beyond the 20 lines granted, Landlord grants Tenant the
right to bring additional lines to its Premises, up to a maximum of 400
additional lines subject to the following terms and conditions:

     (1)   Any additional lines must be in addition to the lines currently
           connected to the Property and be connected at the areas indicated by
           Attachment "A".

     (2)   Tenant agrees that it will be responsible for returning the Premises
           and all penetrations to the building by virtue of such use or
           installation of the phone lines at its sole cost to its original
           conditions to Landlord's sole satisfaction.







                                       12
<PAGE>   13


                                 ATTACHMENT "A"

                             LA COSTA CORPORATE PARK





                                      13

<PAGE>   14


                                    EXHIBIT A

                                 THE "PREMISES"





                                      14


<PAGE>   15


                                    EXHIBIT B

                                  THE "PROJECT"





                                      15

<PAGE>   16


                                    EXHIBIT C

                                  SIGN CRITERIA





                                      16

<PAGE>   17


                                    EXHIBIT D

A.       AGREEMENT

A.1      Landlord and Tenant agree to the construction of improvements in the
         Premises according to the terms and conditions of the Lease, and this
         Exhibit "D."

A.2      Landlord will provide Tenant with final detailed plans and
         specification of all Sole Discretion, subject to the provisions of
         paragraph ____________ Exhibit "D."

A.5      Landlord will complete all final proposed improvements to the best of
         its ability on or before June 10, 1996 subject to the provisions of 
         paragraph D.2 Delays of this Exhibit "D."

B.       TENANT PAID IMPROVEMENTS

         Non-Applicable

C.       METHOD OF PAYMENT

C.1      $N/A is to be paid by Tenant to Landlord subject to the provisions of
         E.3 of this Exhibit "D" in the manner stated below:

         Non-Applicable

D.       DELAYS

D.1      Should Tenant not submit approved final plans and specifications to
         Landlord by the date indicated in paragraph A.3 of this Exhibit "D".
         Landlord will not be subject to any liability and the validity of this
         Lease will not be affected in any way. However, Landlord also reserves
         the right, at its sole discretion, to terminate this Lease.

D.2      The commencement of rent on the date specified in paragraph 1.i. of the
         Lease will not be postponed or waived and Landlord will not be subject
         to any liability if:
     (i) Tenant is the cause of any delay in construction. By way of example,
         including but not limited to: Tenant's request for a delay; the
         installation of Tenant's trade fixture and/or equipment; Tenant's
         request for additional improvements after plans and specifications have
         been approved as described in paragraph A.3,
     (ii)Landlord is unable to complete all improvements by the date indicated
         in A.5 of this Exhibit "D" due to circumstances beyond Landlord's
         reasonable control including but not limited to: requirements by any
         governing authority; shortages; strikes; material delivery delays; or
         acts of God.

E.       ADDITIONAL COSTS

E.1      Any changes required by any governing authority to Tenant approved
         final plans and specifications to conform to local, state or federal
         laws will be at the sole cost of Tenant, in addition to any other
         previously agreed upon improvements costs, if such changes are
         determined to be for the Tenant's special use and not part of the
         general requirements of Landlord to Lease space at the Project, in
         accordance with the provisions of paragraph E.3 of this Exhibit "D".

E.2      Should any changes to previously approved plans and specifications be
         required by Tenant:

     (i) the cost of such revised final plans and specification shall be at the
         sole cost of Tenant.
     (ii)the cost of any changes resulting from such revised plans and
         specifications shall be at the sole cost and expense of Tenant; and
         such charges shall be subject to the provisions of paragraph D and E.3
         of this Exhibit "D".

E.3      Any additional costs including costs of revised construction drawings,
         incurred as a result of the changes described in paragraphs E.1 and E.2
         above, estimated improvement costs, (a) such costs or expenses shall be
         paid by Tenant to Landlord immediately upon receipt by Tenant of
         Landlord's itemized notice, or (b) such costs or expenses shall be
         amortized and included in the Base Monthly Rent for the duration of the
         Lease Term.

F.   LANDLORD'S PAID IMPROVEMENTS




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F.1      Landlord at its sole cost will provide in good and workmanlike
         condition the following improvements as indicated on Exhibit "A":

          1.  Construct wall & add door.
          2.  Construct wall.
          3.  Add door.
          4.  VCT tile areas noted, carpet remainder of office area. 
          5. Landlord will provide the lettering for the initial signage.

          Tenant improvements provided by Landlord shall not exceed $2.50 per
          square foot.








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                                 ATTACHMENT "1"
                             LA COSTA CORPORATE PARK
                            KOLL MANAGEMENT SERVICES
                               RULES & REGULATIONS

1. SIGNS/WINDOWS. All tenant (Lessee) identification signs shall be provided at
the expense of Lessee. No sign, placard, picture advertisement, name or notice
shall be attached to any part of the outside of any building and if so placed
Lessor shall have the right to remove any such sign, placard, picture,
advertisement, name or notice at Lessee's expense. Lessee shall not place or
allow anything to be placed near the glass of any window, door, partition or
wall which may appear unsightly from outside the leased premises, nor conflict
with the above. Lessor will provide a standard drape, blind or window covering
that shall not be altered or removed by Lessee. Lessee is responsible to keep
windows washed, inside and/or out. No awning or shade shall be affixed or
installed over or in the windows or the exterior of the premises.

2. COMMON AREA/ROOF. The sidewalks, entrances and exits, hall passages and
stairways, if any, shall not be obstructed or used by Lessee for any purpose
other than for ingress and egress. The hall passages, exits, entrances,
stairways and roofs are not for the use of the general public and Lessor shall
in all cases retain the right to control and prevent access thereto by all
persons whose presence in the judgment of the Lessor shall be prejudicial to the
safely, character, reputation and interests of the premises and tenants,
provided that nothing herein contained shall be construed to prevent such access
to persons with whom Lessee normally deals in the ordinary course of Lessee's
business unless such persons are engaged in illegal activities. Neither Lessee
nor employees or invitees of Lessee shall go upon the roof of any building.

3. ADVERTISING. Lessee shall not use the name of the building in connection with
or in promoting or advertising the business of Lessee except as to Lessee's
address. Lessor shall have the right to prohibit the use of the name of the
project or other publicity by Lessee which in Lessor's opinion tends to impair
the reputation of the project or its desirability for the Lessees.
Lessees will refrain from or discontinue a such publicity upon notification by
Lessor.

4. LOCKS. No additional locks or bolts shall be placed upon any of the doors or
windows by Lessee, nor shall any changes be made to existing locks or the
mechanisms thereof. Lessee must, upon the termination of Lessee's tenancy,
return to Lessor all keys wither furnished to or otherwise procured by Lessee.
In the event of the loss of any keys so furnished, Lessee shall pay to Lessor
the cost thereof.

5. SOLICITATIONS. Lessee shall not disturb, solicit or canvass any occupant of
the project and shall cooperate to prevent the same.

6. USE OF PREMISES. The leased premises shall not be used for lodging, sleeping
or cooking or for any immoral or illegal purpose or for any purpose that will
damage the premises or the reputation thereof or for any purpose other than that
specified in the lease covering the premises.

7. PARKING. The parking areas within the office park complex shall be used
solely for the parking of passenger vehicles during normal office hours. The
parking of trucks, trailers, recreational vehicles and campers is specifically
prohibited. No vehicle of any type shall be stored in the parking areas at any
time. In the event that a vehicle is disabled, it shall be removed within 48
hours. There shall be no "For Sale" or other advertising signs on or about any
parked vehicle. All vehicles shall be parked in the designated parking areas in
conformation with all signs and other markings. No parking is permitted on
public streets adjacent to the complex.

8. NUISANCES. Lessee shall not use, keep or permit to be used or kept, any foul
or noxious gas or substance in the premises, or permit or suffer the premises to
be occupied or used in a manner offensive or objectionable to Lessor or other
occupants of the building by reason of noise, odors and/or vibrations, or
interfere in any way with other Lessees or those having business therein nor
shall any animals or birds be brought in or kept in or about the premises of the
project. Lessee shall maintain the leased premises free from mice, bugs, and
ants attracted by food, water or storage materials. Lessor is responsible for
maintaining the outside area.

9. DANGEROUS ARTICLES. Lessee shall not use or keep on the premises of the
complex any kerosene, gasoline or inflammable or combustible fluid or material,
or any article deemed extra hazardous on account of fire or other dangerous
properties or u se any other method of heating or air conditioning other than
supplied by Lessor.

10. IMPROPER CONDUCT. Lessor reserves the right to exclude or expel from the
complex any person who in the judgment of the Lessor, is intoxicated or under
the influence of liquor or drugs or who shall in any manner do any act or
violation of the Rules & Regulations of the said project.





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11. WIRING. No electric wires, or any other electrical apparatus, or additional
electrical outlets, shall be installed except with written request to and
written approval from Lessor. Any installation of above wiring shall be removed
by Lessor at Lessee's expense. Lessor reserves the right to enter upon the
leased premises for the purpose of installing additional electrical wiring and
other utilities for the benefit of the Lessee or adjoining tenants. Lessor will
direct electricians as to where and how telephone and telegraph wires are to be
introduced. The location of telephones, call boxes and other equipment affixed
to the premises shall be subject to the approval of Lessor.

12. AUCTION. No auction, public or private, will be permitted.

13. EXTERIOR. Lessee shall not place any improvements or moveable objects
including antennas, outside furniture, etc. in the parking areas, landscaped
area or other areas outside of the leased premises, or on the roof of any
building.

14. SECURITY PRECAUTIONS. All entrance doors in the complex shall be closed and
securely locked when the premises are not in use, and all doors opening to
public corridors shall be kept closed except for normal ingress and egress.
Lessee must observe strict care and caution that all water faucets or any other
apparatus is shut off before Lessee or Lessee's employees leave the premises and
that all electricity, gas, etc. shall likewise be carefully shut off so as to
prevent waste or damage.

15. RESTROOM FACILITIES. The washrooms and restrooms and appurtenances thereto
shall not be used for any other use than those for which they were constructed.
No sweepings, rubbish, rags or other foreign substances shall be thrown or
placed therein. No person shall waste water by interfering or tampering with the
faucets. Any damage resulting in soiled washrooms or restrooms or appurtenances
shall be paid for by the Lessee who, or whose agent, guests, or employees, shall
cause such damage.

16. DAMAGE: Walls, floors and ceilings shall not be defaced in any way and no
one shall be permitted to mark, nail, screw or drill into surfaces, paint or in
any way mar the building surface. Pictures, certificates, licenses and similar
times normally used in Lessee's premises may be carefully attached to the walls
by Lessee in a manner to be proscribed by the Lessor. Upon removal of such items
by Lessee, any damage to the walls or other surfaces shall be repaired by
Lessee.

17. FURNITURE SAFES/MOVING: furniture, freight, equipment, safes or other bulky
articles shall be moved into or out of the complex only in the manner and at
such times as Lessor may direct. Lessee shall not overload the floor of the
premises or in any way deface the premises or any part thereof. Lessor shall in
all cases have the right to determine or limit the weight, size and position of
all safes and other heavy equipment. Lessor will not be responsible for loss or
damage to any safe or other properly shall be repaired at the expense of Lessee.

18. JANITORIAL SERVICE. Lessee shall not cause any unnecessary labor by reason
of Lessee's carelessness or indifference in the preservation of good order and
cleanliness. Lessor shall not be responsible to Lessee for any loss of property
on the premises, however occurring or for any damage done to the effect of
Lessee by the janitor or any other employee or any other person.

19. REQUIREMENTS OF LESSEE. Employees of Lessor shall not perform any work or do
anything outside of their regular duties unless under special instruction from
Lessor. Lessee shall give Lessor prompt notice of any defects in the water,
sewage, gas pipes, electrical lights and fixtures, heating apparatus, or any
other service equipment.

20. RULES AND REGULATIONS: Rules may be modified, amended or supplemented at any
time by Lessor upon notice to Lessee.






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