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                                                                    EXHIBIT 10.1

1.       BASIC LEASE PROVISIONS:

<TABLE>
<S>                                                   <C>
A.       Building Address:                            2101 So. Arlington Heights Road
                                                      Arlington Heights, Illinois  60005

B.       Landlord and Address:                        LaSalle Bank National Association, Successor Trustee
                                                      to American National Bank and Trust Company of
                                                      Chicago As Trustee Under Trust No. 59948

                                                      c/o Liz-Green, Inc.
                                                      2101 So. Arlington Heights Road
                                                      Arlington Heights, Illinois  60005

C.       Tenant and Current Address:                  Security Associates International, Inc.
                                                      ----------------------------------------------------
                                                      2101 So. Arlington Heights Rd.  #100
                                                      ----------------------------------------------------
                                                      Arlington Heights, Illinois  60005
                                                      ----------------------------------------------------

D.       Date of Lease:                               August 12, 2000
                                                      ----------------------------------------------------

E.       Length of Lease Term:                        Ten (10) years
                                                      ----------------------------------------------------

F.       Commencement Date of Term:                   January 1, 2001
                                                      ----------------------------------------------------

G.       Expiration Date of Term:                     December 31, 2010
                                                      ----------------------------------------------------

H.       Annual Net Base Rent:                        See Exhibit "A"
                                                      ----------------------------------------------------

I.       Actual Combined Operating
         & Real Estate Tax Adjustment:                See Exhibit "A"
                                                      ----------------------------------------------------

J.       Rentable Area of Premises:                   18,233   Square Feet
                                                      ----------------------------------------------------

K.       Rentable Area of Building:                   61,733  Square Feet
                                                      ----------------------------------------------------
L.       Tenant's Proportionate
         Share:                                       29.54% (Percent)
                                                      ----------------------------------------------------
M.       Security Deposit:                            None

N.       Suite Numbers of Premises:                   Suite #150 and Suite #145
                                                      ----------------------------------------------------

O.       Broker                                       Liz-Green, Inc.
                                                      ----------------------------------------------------

P.       Exhibits:                                    Exhibit A - Annual Rent Schedule
                                                      ----------------------------------------------------
                                                      Exhibit B - Cleaning Specifications
                                                      ----------------------------------------------------
                                                      Exhibit C - Rules & Regulations
                                                      ----------------------------------------------------
                                                      Exhibit D - Space Plan Of Premises
                                                      ----------------------------------------------------
                                                      Exhibit E - Scope Of Work Clarifications
                                                      ----------------------------------------------------
</TABLE>


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2. LEASING AGREEMENT. LaSalle Bank National Association, Successor Trustee to
American National Bank and Trust Company of Chicago, As Trustee Under Trust No.
59948 (the "Landlord") and the beneficiaries of a certain Trust Agreement dated
December 15, 1983, and known as Trust Number 59948 at LaSalle Bank National
Association (the "Beneficiary") leases to Tenant and Tenant leases from Landlord
the premises (the "Premises") which are or will be contained in the building
(the "Building") located at 2101 South Arlington Heights Road, Arlington
Heights, Illinois 60005. The terms of this lease (the "Term") shall commence on
the date (the "Commencement Date") which is the earlier to occur of the date
stated in Paragraph lF, or the date Tenant first occupies all or part of the
Premises for the conduct of business. The Term shall expire on the date (the
"Expiration Date") stated in Paragraph 1G, unless terminated earlier as
otherwise provided in this Lease.

3. SERVICES.

A. Basic Services. Landlord shall furnish the following services, subject to
applicable laws and governmental restrictions and to the other provisions of
this Lease:

(1) Cooled and heated air in season of all common areas within the Building,
daily from 7:30 A.M. to 6:00 P.M. (Saturdays from 8:00 A.M. to 1:00 P.M.),
Sundays and holidays excepted. These utility costs are a part of the Building's
operating expense as more fully described in 7.A.(1).

(2) Customary maintenance and repair of the exterior portion of the Building
(including the roof), the parking area for the Building, the common areas of the
Building and, subject to Tenant's obligations under subsections (1), (2) and (3)
of Paragraph 3B below, the structural, mechanical, plumbing and electrical
systems of the Building.

(3) Cold water for drinking, lavatory and toilet purposes drawn through fixtures
installed by Landlord, or by Tenant with Landlord's written consent and hot
water for lavatory purposes drawn from regular Building supply at the prevailing
temperatures. Tenant shall pay Landlord at rates fixed by Landlord for water
furnished for any other purpose.

(4) Customary janitor service in and about the common areas within the Building,
Monday through Friday; Saturdays, Sundays and holidays excepted. Attached to
this Lease as Exhibit "B" are the current cleaning specifications for the
Building, all of which Tenant hereby agrees shall be deemed to be reasonable.

(5) Washing of the windows in the common areas of the Building and washing of
the exterior windows in the Premises shall be furnished periodically at such
times as Landlord in its discretion shall determine.

(6) Lighting of common areas of the Building's West wing during the Building's
normal hours will be as specified in subsection (1) of this Paragraph 3A.
Lighting of common areas of the Building's East wing will remain on (24) twenty
four hours per day, (7) seven days per week. Parking lot lighting of exterior
parking lot at Building's East wing shall have those light standards illuminated
as required by time of year from 5:00 p.m. to 9:00 a.m. C.S.T.

(7) Clearance of snow from the parking lot and sidewalks serving the Building at
such times as Landlord in its discretion shall determine.

(8) Landscaping of the plants and foliage in the common areas of the Building at
such times as Landlord in its discretion shall determine.

(9) Exterior paved parking area with spaces available for Tenant's use on a
first-come, first-serve basis and for use by Landlord and its agents and other
tenants, guests and invitees, including rubbish removal and cartage in and about
the premises Mondays through Saturday both inclusive, Sundays and holidays
excluded.


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<PAGE>   3

B. Tenant's Utilities and Certain Services.

(1) Electricity shall not be furnished by Landlord, but shall be furnished by
the approved electric utility company serving the Building. Landlord shall
permit Tenant to receive such service directly from such utility company at
Tenant's cost and shall permit Landlord's wire and conduits, to the extent
available, suitable and safely capable, to be used for such purposes. The
Premises shall contain two (2) electrical meters installed at Landlord's
expense, one for heating and air conditioning and the other for lighting and
outlets. Tenant shall make all necessary arrangements with the utility company
for paying for electric current furnished by the utility company to the Premises
and Tenant shall pay for all charges for all electric current consumed in the
Premises, including without limitation, performance of janitor service, the
making of any alterations or repairs in the Premises, the operation of all
heating, ventilating and air conditioning systems and the operation of all other
systems which may be required for telephone or data processing equipment, and
for other special equipment or machinery installed by Tenant.

(2) Tenant agrees to purchase from Landlord, all lamps, bulbs, ballast's and
starters used in the Premises after the initial installation of same.

(3) Heating and air conditioning equipment currently installed servicing the
Premises shall be repaired and maintained at Landlord's sole cost, this also
includes replacement of filters within the heating and air conditioning
equipment. Tenant shall maintain a temperature in the Premises at all times
during the Term of not less than 55 degrees Fahrenheit. In the event any heating
or air conditioning equipment servicing the Premises requires replacement as a
result of Tenant's failure to permit Landlord to perform its obligations under
this subsection (3) of Paragraph 3B or to notify Landlord of any malfunction or
other problem of such equipment, then Tenant also shall bear the cost of the
replacement of such equipment.

(4) Heating and air conditioning equipment to be installed by Tenant which will
serve the to be constructed UPS room and Call Center rooms will be repaired and
maintained at the sole cost of the Tenant.

(5) Any emergency back up generators and UPS systems shall repaired and
maintained at the sole cost of the Tenant.

(6) Tenant shall make arrangements directly with the Telephone company servicing
the Building for such telephone service in the Premises as is, desired by Tenant
and the cost of all such telephone service (including the cost of installing all
wires and cables) shall be paid for by Tenant.

(7) If Tenant desires telegraphic, burglar alarm, computer installations or
signal service, Landlord shall upon request of Tenant direct where and how all
connections for such service shall be introduced and run. In the absence of such
directions, Tenant shall make no borings, cutting or installation of wires or
cables in or about the Premises. The cost of all such installations and service
shall be paid for by Tenant.

C. Additional Services. Landlord shall in no event be obligated to furnish any
services or utilities, other than those stated in Paragraph 3A. If Landlord
elects to furnish services or utilities requested by Tenant in addition to those
stated in Paragraph 3A (including utility services in the common areas of the
Building at times other than those stated in Paragraph 3A), Tenant shall pay to
Landlord Landlord's then prevailing charges for such services and utilities
within thirty (30) days after receipt of Landlord's statements. If Tenant shall
fail to make any such payment, Landlord may, without notice to Tenant and in
addition to all other remedies available to Landlord, discontinue any or all of
the additional services. No discontinuance of any service under this Paragraph
3C shall result in any liability of Landlord to Tenant or be considered as an
eviction or a disturbance of Tenant's use of the Premises.

D. Failures or delays in furnishing services.

(1) Tenant agrees that Landlord shall not be liable for damages for any failure,
delay or interruption in the furnishing of any of the services described in
Paragraphs 3B or 3C above, if such failure delay or interruption shall be
remedied within 96 hours and that during such periods, the interior temperature
of the Premises shall not exceed 90 degrees F nor fall below 55 degrees F.


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(2) Tenant agrees that Landlord shall not be liable for damages for any failure
to furnish or delay in furnishing any service stated in Paragraph 3A if such
failure or delay is caused, in whole or in part, by any one or more of the
events stated in Paragraph (24 I).

(3) No failure or delay in furnishing any service stated in Paragraph 3A, 3B or
3C caused in whole or in part by any one or more of the events stated in
Paragraph (24 I), shall not be considered to be an eviction or disturbance of
Tenant's use of the Premises, or relieve Tenant from its obligation to pay all
Rent when due or from any other obligations of Tenant under this Lease provided
such failure shall not result in a health or safety hazard, exceed 96 hours in
duration or result in temperatures exceeding 90 degrees F nor falling below 55
degrees F.

4. POSSESSION, USE AND ENJOYMENT.

A. Possession and Use of Premises. Tenant shall be entitled to possession of the
Premises on January 01, 2001. Tenant shall occupy and use the Premises for
general office purposes only, with the exception of approximately (2,000) two
thousand square feet in the Eastern portion of the Leased Premises which shall
be used as a call center that will be operated on a (24) twenty four hour (7)
seven day per week basis. Tenant shall not occupy or use the Premises or permit
the use or occupancy of the Premises for any purpose or in any manner which:

(1) may be dangerous to persons or property;

(2) may invalidate or increase the amount of premiums for any policy of
insurance affecting the Building, and if any additional amounts of insurance
premiums are so incurred, Tenant shall pay to Landlord the additional amounts on
demand; or

(3) may create a nuisance, disturb any other tenant of the Building or the
occupants of neighboring property or injure the reputation of the Building.

B. Quiet Enjoyment. Provided that Tenant is not in breach or default under this
Lease, Tenant shall be entitled to peaceful and quiet enjoyment of the Premises,
subject to the terms of this Lease.

5. CONDITION OF PREMISES. Tenant shall notify Landlord in writing within thirty
(30) days after Tenant takes possession of the Premises of any defects in the
Premises claimed by Tenant. Except for defects stated in such notice and latent
defects of which Tenant becomes aware and notifies Landlord after the
Commencement Date, Tenant shall be conclusively presumed to have accepted the
Premises in the condition existing on the date Tenant first takes possession and
to have waived all claims relating to the condition of the Premises. No
agreement of Landlord to alter, remodel, decorate, clean or improve the Premises
or the Building, and no representation regarding the condition of the Premises
or the Building has been made by or on behalf of Landlord to Tenant, except as
stated in this Lease. In addition to and without limitation of Tenant's
obligations under subsection (3) of Paragraph 3B above, Tenant, at its expense,
shall keep the Premises in good repair and operating condition and shall
promptly repair all damage to the Premises caused by Tenant, or any of its
employees, agents or invitees.

6. NET BASE RENT. Tenant shall pay to Landlord Net Base Rent during the Term at
the annual rate(s) stated in Paragraph 1H. Net Base Rent shall be payable in
equal monthly installments in advance on the first day of each calendar month
during the Term, except that the installment of Net Base Rent due for the first
month of the Term in which Net Base Rent is payable shall be paid by Tenant to
Landlord when Tenant signs this Lease.

7. RENT ADJUSTMENT.

A. Definitions. As used in this Lease:

(1) "Expenses" shall mean and include all expenses, costs, fees and
disbursements paid or incurred by or on behalf of Landlord for owning, managing,
operating, maintaining and repairing the Building, the land upon which the
Building is situated (the "Land") and the personal property and equipment used
in connection with the Building or the Land. Expenses shall include the cost of
any capital improvements to the Building made after the date of this Lease which
are intended to reduce Expenses or which are required under any governmental
laws, regulations or ordinances which were not applicable to the Building at the
time it was constructed, which cost shall be


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amortized over such reasonable period as Landlord shall determine, together with
interest on the un-amortized cost of any such improvement (at the prevailing
loan rate available to Landlord on the date the cost of such improvement was
incurred). Expenses shall not include "Taxes" (as defined in Paragraph 7.A. (2),
costs of alterations of the premises of tenants of the Building, interest and
principal payments on mortgages, ground rental payments and real estate
brokerage and leasing commissions and activities for the sole purpose of
marketing or leasing.

(2) "Taxes" shall mean any and all charges that are evidenced by the semi annual
real estate tax bills issued by the Cook County Collectors Office or any other
agency empowered to render a real estate tax bill for the Building.

(3) "Tenant's Proportionate Share" shall mean the percentage stated in Paragraph
1L. Tenant's Proportionate Share is determined by dividing the rentable area of
the Premises (which the parties mutually agree contains the area stated in
Paragraph 1J) by the rentable area of the Building (which the parties mutually
agree contains the area stated in Paragraph 1K.

B. Rent Adjustment. In addition to Base Rent, Tenant shall pay to Landlord for
each calendar year occurring entirely or partially within the Term (herein
sometimes called "Rent Adjustment"), Tenant's Proportionate Share of the sum of
all Expenses plus all Taxes for such calendar year as listed on Page 1, Item I
of the Basic Lease Provisions.

C. Payments of Rent Adjustment. Tenant shall make payments ("Progress Payments")
on account of the Combined Expense and Tax Adjustment for each calendar year
occurring entirely or partially within the Term as follows. Landlord may furnish
to Tenant prior to such calendar year and from time to time during such calendar
year a written notice (a "Projection Notice") setting forth (i) Landlord's
reasonable estimates, forecasts or projections of Taxes and Expenses for such
calendar year, (ii) the Combined Expense and Tax Adjustment for such calendar
year based upon such projections, and (iii) the monthly Progress Payments to be
made by Tenant for such year based upon such projected Combined Expense and Tax
Adjustment. Until Landlord furnishes a Projection Notice for such calendar year,
Tenant shall pay to Landlord Progress Payments (at the time of and together with
each monthly installment of Base Rent) equal to the greater of the latest
monthly installment of Progress Payments or one-twelfth (1/12th) of the sum of
the latest actual Combined Expense and Tax Adjustment as determined by Landlord.
On or before the first day of the month immediately following service of a
Projection Notice, and on or before the first day of each following month until
Tenant receives a further Projection Notice, Tenant shall pay to Landlord the
monthly installment of Progress Payments shown in the Projection Notice. Within
thirty (30) days following service of a Projection Notice, Tenant shall also pay
to Landlord a lump sum payment equal to the Progress Payments owing by Tenant to
Landlord (as shown in the Projection Notice) for the period commencing on the
first day of such calendar year and expiring on the last day of the month during
which such Projection Notice is served, less all Progress Payments previously
paid by Tenant to Landlord for such calendar year.

D. Readjustments. After the end of each calendar year and after Landlord shall
have determined the actual amounts of Taxes and the actual amount of Expenses to
be used in determining the Combined Expense and Tax Adjustment for such calendar
year, Landlord shall furnish Tenant a statement ("Landlord's Statement") of
Taxes and Expenses and the Combined Expense and Tax Adjustment for such calendar
year. If the sum of the Combined Expense and Tax owed for such calendar year
exceeds the Progress Payments paid by Tenant to Landlord for such calendar year,
then Tenant shall pay to Landlord within thirty (30) days after the date of
Landlord's Statement, an amount equal to such excess. If the Progress Payments
paid by Tenant to Landlord for such calendar year exceed the sum of the Combined
Expense and Tax Adjustment owed for such calendar year, then Landlord shall
credit such excess to Rent payable after the date of Landlord's Statement until
such excess is exhausted. If this Lease shall expire or terminate prior to full
application of such excess, Landlord shall pay to Tenant the unapplied balance
that is not reasonably required for payment of Rent Adjustment for the calendar
year in which the Lease expires or terminates. No interest or penalties shall
accrue on any amounts which Landlord is obligated to credit or pay to Tenant by
reason of this Paragraph 7D. Unless Tenant shall take written exception to any
item shown in any Landlord's Statement within thirty (30) days after the date of
such Landlord's Statement, Landlord's Statement shall be considered as final and
conclusively binding upon Tenant.

E. Survival. The obligations of Tenant to pay Rent Adjustment provided for in
this Paragraph 7 shall survive the expiration or termination of this Lease.
Tenant shall pay any Rent Adjustment owing to


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Landlord within fifteen (15) days after the date of Landlord's Statement for the
calendar year in which this Lease expires or terminates.

F. No Decrease in Base Rent. In no event shall the determination of any Rent
Adjustment owing under this Paragraph 7 result in a decrease in the Net Base
Rent stated in Paragraph 1H.

G. Books and Records. Landlord shall maintain books and records of Expenses and
Taxes in accordance with sound accounting and managing practices. Provided that
all Rent (including Rent Adjustment) has been paid in full and Tenant is not
otherwise in breach or default under this Lease, the books and records shall be
available to Tenant for inspection during Landlord's normal business hours upon
prior reasonable notice at a location designated by Landlord.

H. Payment of Rent. All charges, costs and sums required to be paid by Tenant
under this Lease in addition to Net Base Rent and Rent Adjustment shall be
considered additional rent, and Base Rent, Rent Adjustment and additional rent
shall be collectively called "Rent". Rent shall be payable without demand,
notice, offset or deduction, except as otherwise specifically stated in this
Lease. All Rent due under this Lease shall be paid by checks payable to the
order of Arlington Associates, and delivered to Liz-Green, Inc., the managing
agent ("Manager"), which checks shall be mailed or delivered to Manager at the
Office of Manager, 2101 So. Arlington Heights Road, Arlington Heights, Illinois
60005 or in such other manner or at such other place as Landlord or Beneficiary
may from time to time designate to Tenant. Net Base Rent and Rent Adjustment
will be prorated for partial months or years within the Term. Tenant's covenant
to pay Rent shall be independent of each and every other covenant and provision
of this Lease.

8. SECURITY DEPOSIT. None.

9. ALTERATIONS.

A. Approvals. Without Landlord's prior written consent (which consent shall not
be unreasonably withheld), Tenant shall not make or cause to be made any
alterations, improvements, additions, changes or repairs (an "alteration",
collectively) in or to the Premises or the Building. As a condition to granting
its consent to any alteration, Landlord may impose reasonable requirements,
including, without limitation, requirements as to the manner and time for the
performance of such alteration and the type and amount of insurance and bonds
Tenant must acquire and maintain during the course of performance of such
alteration. In addition, Landlord shall have the right to: approve the
contractors or mechanics performing the alteration; approve all plans and
specification for the alteration; review the work of Tenant's architects,
engineers, contractors or mechanics; such approval shall not be unreasonably
withheld. The Landlord may order reasonable changes in such alteration in
instances in which materials or workmanship is defective or not in accordance
with plans or specifications previously approved by Landlord. Tenant shall pay
the entire cost of an alteration, and if requested by Landlord, shall deposit
with Landlord prior to commencement of such alteration, funds or other security
reasonably acceptable to Landlord covering the full cost of such alteration.
Each alteration shall become the property of Landlord when made and shall be
surrendered with the Premises upon the expiration or termination of this Lease;
provided, however, that Landlord may, by written notice to Tenant, require
Tenant, at its expense, to remove any or all alterations, including but not
limited to the UPS system, exterior diesel generator, exterior antennas and all
associated electrical panels and feeders and repair any damage to the Premises
or Building caused by such removal, prior to the expiration or termination of
this Lease.

B. Compliance with Laws. Each alteration shall be performed in a good and
workmanlike manner using new grades of materials; in full compliance with all
applicable laws, ordinances and governmental regulations, rules and
requirements; and in full compliance with all insurance rules, orders,
directions, regulations and requirements.

C. No Liens. Before any alteration is commenced, Tenant shall give Landlord at
least fifteen (15) days' prior written notice of same. Tenant, at its expense,
shall procure and deliver to Landlord a completion and lien indemnity bond
satisfactory to Landlord for such alteration, and during the course of
performance of such alteration Tenant shall, upon Landlord's request, furnish
Landlord with sworn contractor's statements and lien waivers covering all work
previously performed. Tenant shall not permit any lien or claim for lien of any
mechanic, laborer or supplier or any lien to be filed against the Building or
the Land, or any part thereof arising out of work performed, or alleged to have
been performed by, or at the direction of, or on behalf of Tenant. If any such
lien or claim for lien is filled, Tenant shall within ten (10) days after
written request to Tenant, either (i) have such lien or claim for lien released
of record, (ii) deliver


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to Landlord a bond in form, content, amount, and issued by surety, satisfactory
to Landlord indemnifying Landlord and others designated by Landlord against all
costs and liabilities resulting from such lien or claim for lien and the
foreclosure or attempted foreclosure thereof, or (iii) at Tenant's sole expense,
obtain and deliver to Landlord, a commitment from Chicago Title Insurance
Company, or other title insurance company acceptable to Landlord, committing to
insure title to the Building and the Landlord over such lien, in favor of
Landlord or any proposed purchaser or mortgagee of said Land or the Building. If
Tenant fails to have such lien, or claim for lien so released, or to deliver
such bond or title insurance commitment to Landlord, Landlord, without
investigating the validity of such lien, may pay or discharge the same and
Tenant shall reimburse Landlord upon demand for the amount so paid by Landlord,
including Landlord's expenses and attorney's fees. Tenant agrees to indemnify,
hold harmless and defend Landlord, the Beneficiary, the Manager and their
respective officers, partners and employees from any liability, loss, cost,
damage or expense (including attorneys' fees), arising out of any such lien
claim or out of any other claim relating to work done or materials supplied to
the Premises at Tenant's request or on Tenant's behalf, except if work is
furnished and installed by Landlord.

10. ASSIGNMENT AND SUBLETTING.

A. Consent. Tenant shall not without the prior written consent of Landlord which
consent shall not be unreasonably with-held in each instance,

(1) assign, mortgage, pledge, hypothecate or otherwise transfer or permit the
transfer of this Lease or the interest of Tenant in this Lease, in whole or in
part, by operation of law or otherwise:

(2) sublet all or any part of the Premises; or

(3) permit the use or occupancy of all or any part of the Premises for any
purpose not permitted under Paragraph 4, or by anyone other than Tenant and
Tenant's employees.

For purposes of this Paragraph 10A an "assignment" shall be considered to
include a change in the majority ownership or control of Tenant if Tenant is a
corporation whose stock is not traded publicly.

B. Recapture of Space. If Tenant desires to assign this Lease or sublet all or
any part of the Premises, Tenant shall give Landlord written notice ("Tenant's
Notice") of such desire prior to entering into such assignment or sublease,
which Tenant's Notice shall be signed by an officer or partner of Tenant. If
Tenant's Notice is for a proposed assignment, it shall state the name, address
and business of the assignee (and include current credit information and reports
on such assignee); the effective date of assignment; and the amount of all sums
and other consideration to be paid or transferred to Tenant for such assignment.
If Tenant's Notice is for a proposed sublease, it shall state the name, address
and business of the subtenant (and include current credit information and
reports on such subtenant); the commencement date of the term of the sublease;
the length of the term of the sublease (including any renewal options); the rent
to be payable under the sublease; and shall include a floor plan showing the
part of the Premises to be sublet (including separate identification of any part
of the Premises for which the subtenant will be granted expansion options or
rights). Landlord shall then have the right (the "recapture right") to (i)
terminate this Lease in its entirety effective as of the proposed effective date
of assignment or the proposed commencement date of the term of the sublease (as
specified in Tenant's Notice), if Tenant's Notice is for a proposed assignment
or for a proposed sublease of all of the Premises; or (ii) partially terminate
this Lease effective as of the proposed commencement date of the term of the
sublease (as specified in Tenant's Notice), with respect to that part of the
Premises to be sublet, if Tenant's Notice is for a proposed sublease of less
than all of the Premises. Landlord may exercise the recapture right by giving
Tenant written notice ("Landlord's Notice") of such exercise within fifteen (15)
business days after receipt by Landlord of Tenant's Notice. If Landlord
exercises the recapture right and this Lease is terminated in its entirety, then
neither Landlord nor Tenant shall have any further rights, estates or
liabilities under this Lease accruing after the effective date of termination,
except for such obligations which expressly survive the termination of this
Lease. If Landlord exercises the recapture right and this Lease is partially
terminated with respect to a part of the Premises (the "excluded space"), then,
effective as of the date this Lease is so partially terminated (i) the Net Base
Rent stated in Paragraph 1H shall be decreased to the product obtained by
multiplying such amount by a fraction, the numerator of which is the rentable
area of the Premises immediately after such partial termination of this Lease
(as determined by Landlord) and the denominator of which is the rentable area of
the Premises immediately prior to such partial termination of this Lease, (ii)
the rentable area of the Premises stated in Paragraph 1J shall be reduced by the
rentable area of the excluded space, (iii) Tenant's Proportionate Share stated
in Paragraph 1L shall be reduced to the percentage


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obtained by dividing the new rentable area of the Premises by the rentable area
of the Building, (iv) Tenant shall pay the reasonable costs incurred in
physically separating the excluded space from the balance of the Premises and
shall surrender the excluded space to Landlord on or before the effective date
of partial termination in a good, clean and tenantable condition, ordinary wear
excepted; and (v) neither Landlord nor Tenant shall have any further rights,
estates or liabilities under this Lease with respect to the excluded space
accruing after the effective date of partial termination of this Lease, except
for such obligations which expressly survive the termination of this Lease.

C. Conditions for Consent. If Landlord does not exercise any recapture right
arising in favor of Landlord under Paragraph 10B, Tenant may then enter into the
assignment or sublease, as the case may be, specified in the Tenant's Notice
giving rise to such recapture right, in accordance, and only in accordance, with
the following provisions. If Tenant enters into such assignment or sublease it
shall submit an executed copy of the sublease or assignment to Landlord for
consent not less than thirty (30) days prior to the proposed effective date of
assignment or the proposed commencement date of the term of the sublease, as the
case may be. In the case of a sublease, the instrument shall expressly state
that it is and shall remain at all times subject and subordinate to this Lease
and all of the terms, covenants and agreements contained in this Lease. No such
assignment or sublease instrument shall expressly or by implication impose upon
Landlord any duties or obligations or alter the provisions of this Lease.
Landlord agrees to give Tenant written notice within fifteen (15) days after
receipt by Landlord of Tenant's proposed assignment or proposed sublease of
Landlord's consent to or rejection of same. Landlord agrees that its consent to
any such proposed assignment or proposed sublease shall not be unreasonably
withheld; provided, however, that in addition to other circumstances under which
Landlord's consent may be withheld, Tenant agrees that the withholding by
Landlord of its consent to such proposed assignment or proposed sublease will
not be deemed "unreasonable" if:

(1) the assignee or subtenant is non-creditworthy or disreputable, or is not of
a character, or otherwise is not in keeping with, the nature or class of tenants
in the Building,

(2) the assignee or subtenant is a government (or subdivision or agency thereof)
or is then a tenant in the Building,

(3) the use of the Premises by the assignee or subtenant would, in Landlord's
reasonable judgment, significantly increase the pedestrian traffic in and out of
the Building or the vehicular traffic in and about, or the use of, the exterior
paved parking area, or would require Landlord to perform any alterations to the
Building to comply with applicable building code requirements,

(4) there is then in existence any sublease of all or any part of the Premises,
or

(5) Tenant is then in breach or default under this Lease.

Tenant may not submit to Landlord for consent any assignment or sublease on
terms or conditions or with parties different from those stated in the Tenant's
Notice for such assignment or sublease, nor may Tenant submit to Landlord for
consent any assignment or sublease later than the date which is sixty (60) days
after the expiration of the period for exercise by Landlord of the recapture
right arising by reason of such assignment or sublease, without the right to
exercise its recapture right. Notwithstanding anything to and contrary contained
in this Lease, Tenant's sole right and remedy in any dispute as to whether
Landlord's consent to a proposed sublease or proposed assignment has been
unreasonably withheld shall be action for declaratory judgment or specific
performance and Tenant shall not be entitled to any damages if Landlord is
adjudged to have unreasonably withheld such consent.

D. Profit. If Tenant, having first obtained Landlord's consent in accordance
with Paragraph 10C, shall assign this Lease for money or other property, or
sublet all or any part of the Premises at a rental or for other consideration in
excess of the Net Base Rent plus Rent Adjustment (or prorate portion thereof)
due and payable by Tenant under this Lease, then Tenant shall pay to Landlord,
as additional rent (i) on the first day of each month during the term of any
such sublease, the excess of all rent and other consideration due from the
subtenant for such month over the sum of (ii) the Net Base Rent plus Rent
Adjustment then payable to Landlord under this Lease for said month (or if only
a portion of the Premises is being sublet, the portion of the Net Base Rent plus
Rent Adjustment then payable to Landlord under this Lease for said month which
is allocable on a square footage basis to the space sublet), plus (iii) an
amount equal to the quotient of the reasonable leasehold improvement costs and
customary real estate brokerage commissions to licensed Illinois real estate
brokers (other than to "Tenant or any affiliate of Tenant) incurred by Tenant


                                       9
<PAGE>   9

in connection with such sublease (as shall be supported by appropriate written
documentation submitted by Tenant to Landlord), divided by the number of months
in the term of such sublease, and (iv) immediately upon receipt, all sums or
other consideration received by Tenant from any such assignment; it being
agreed, however, that Tenant shall be responsible to Landlord for any deficiency
if Tenant shall assign this Lease or sublet all or any part of the Premises at a
rental or for consideration which is less than that required under this Lease.

E. No Waiver. Consent by Landlord to any subletting, transfer, lien, charge, use
or occupancy, shall not operate as a waiver by Landlord of, or to release or
discharge Tenant from, any liability under this Lease, whether past, present or
future (including liability arising during any renewal term of this Lease or
with respect to any expansion space included in the Premises), or be considered
to be a consent to or relieve Tenant from obtaining Landlord's consent to any
subsequent assignment, subletting, transfer, lien, charge, use or occupancy.
Tenant shall pay Landlord's reasonable costs, charges and expenses, including
attorney's fees and fees of architects, engineers and other professionals,
incurred in connection with its review of any proposed assignment or proposed
sublease, whether or not Landlord approves such transfer of interest, which in
no event shall be more than five hundred dollars ($500.00) for each proposed
sublease or assignment.

11. WAIVER AND INDEMNITY.

A. Waiver. To the extent permitted by Illinois law, Tenant waives all claims
against Landlord, the Beneficiary, the property manager and their respective
officers, partners, agents and employees, for injury or damage to person or
property sustained by Tenant resulting directly or indirectly from the gross
negligence or willful misconduct of Tenant, their respective officers, partners,
agents and employees due to fire or other casualty, cause or any existing or
future condition, defect, matter or thing in or about the Premises or the
Building, or from any equipment or appurtenance in the Building, or from any
accident in or about the Building, or from any act or neglect of any tenant or
other occupant of the Building or of any other person. This Paragraph 11A shall
apply especially, but not exclusively, to damage caused by water, snow, frost,
steam, excessive heat or cold, sewerage, gas, odors or noise, or the bursting or
leaking of pipes or plumbing fixtures, broken glass, sprinkling or air
conditioning devices or equipment, or flooding, and shall apply without
distinction as to the person whose act or neglect was responsible for the damage
and whether the damage was due to any of the acts specifically enumerated above,
or from any other thing or circumstance, whether of a like nature or of a wholly
different nature.

B. Indemnity. Tenant agrees to indemnify and hold harmless Landlord, and
Beneficiary, the Manager and their respective officers, partners, agents, and
employees, from and against any and all claims, demands, actions, injuries to
all persons and damage to or theft or misappropriation or loss of property
occurring in or about the Premises and arising from Tenant's occupancy of the
Premises or the conduct of its business or from any activity, work, or thing
done, permitted or suffered by Tenant in or about the Premises or from any
breach or default on the part of Tenant in the performance of any covenant or
agreement on the part of Tenant to be performed under this Lease or due to any
other act or omission of Tenant, its agents or employees. If any such proceeding
is filed against Landlord or any such indemnified party, Tenant agrees to defend
such proceeding at its sole cost by legal counsel reasonable satisfactory to
Landlord, if requested by Landlord.

12. LANDLORD'S REMEDIES.

A. Events of Default. Each of the following shall constitute an "event of
default" by Tenant under this Lease:

(1) Tenant fails to pay any installment of Rent within five (5) days after such
installment of Rent is due (which five (5) day period shall run concurrently
with and not be in addition to the statutory Landlord's five (5) day notice
required under Illinois law in dispossession proceedings); provided, however,
that if in any consecutive twelve (12) month period Tenant shall, on three (3)
separate occasions, fail to pay any installment of Rent on the date such
installment of Rent is due, then on the fourth (4th) such occasion and on each
occasion thereafter on which Tenant shall fail to pay an installment of Rent on
the date such installment of Rent is due, each such failure shall constitute an
event of default and Tenant shall then no longer have any five (5) day period in
which to cure any such failure.


                                       10
<PAGE>   10

(2) Tenant fails to observe or perform any of the other covenants or provisions
of this Lease to be observed or performed by Tenant and, for each such failure
which has not previously occurred within the then preceding six (6) month
period, Tenant fails to cure such failure within fifteen (15) days after written
notice to Tenant; provided, that if such failure is not susceptible to being
cured within such fifteen (15) day period but Tenant promptly commences such
cure, said fifteen (15) day period shall be extended as long as Tenant is
actively, diligently and continuously attempting to effectuate such cure (and
furnishing Landlord with weekly written status reports on such efforts) but in
no event shall said fifteen (15) day period be extended by more than thirty (30)
days;

(3) Tenant fails to maintain a temperature in the Premises of not less than
fifty-five degrees (55 degrees) Fahrenheit as provided in subsection (3) of
Paragraph 3B Above.

(4) Tenant abandons the Premises.

B. Landlord's Remedies. Upon the occurrence of an event of default by Tenant
under this Lease, Landlord, at its option, without further notice or demand to
Tenant, may, in addition to all other rights and remedies provided in this
Lease, or available to Landlord at law or in equity:

(1) Terminate this Lease and Tenant's right to possession of the Premises and
recover all damages to which Landlord is entitled under law, and in such event,
Landlord shall, to the extent required by law, take reasonable measures to
mitigate damages recoverable against Tenant. Landlord's damages shall
specifically include, without limitation (a) all Landlord's expenses or
re-letting including repairs, alterations, improvements, additions, legal fees
and brokerage commissions), plus (b) the amount of all Rent owing under this
Lease for the balance of the Term discounted at the rate of six percent (6%) per
year, which amount shall be automatically considered accelerated and immediately
due and payable in full by Tenant to Landlord upon Landlord's election to
terminate this Lease.

(2) Terminate Tenant's right to possession of the Premises without terminating
this Lease, in which event Landlord shall, if and to the extent required by law,
take reasonable measures to mitigate the damages recoverable against Tenant by
attempting to relet the Premises or any part thereof for the account of Tenant,
for such rent and term and upon such terms and conditions as are acceptable to
Landlord; provided, however, that Landlord shall not be obligated to market or
relet the Premises on a priority basis over unleased or unoccupied space in the
Building or to relet the Premises to any person or entity that falls within the
categories specified in 10C (1), (2) or (3) of this Lease. For purposes of such
re-letting, Landlord is authorized to decorate, repair, alter and improve the
Premises to the extent reasonably necessary. If Landlord does not relet the
Premises, then Tenant shall pay Landlord monthly on the first day of each month
during the period that Tenant's right of possession is terminated, a sum equal
to the amount of Rent due under this Lease for such month (less any amount which
Landlord could have realized if Landlord relet the Premises to a reputable,
credit worthy substitute tenant procured by Tenant and presented to Landlord in
writing, which substitute tenant was ready, willing and able to lease the entire
Premises from Landlord under a lease in form identical to the form of this
Lease). If the Premises are relet and a sufficient sum is not realized from such
reletting after payment of all Landlord's expenses of re-letting (including
repairs, alterations, improvements, additions, decorations, legal fees,
advertising and other marketing expenses and brokerage commissions) to satisfy
the payment of Rent due under this Lease for any month, Tenant shall pay
Landlord any such deficiency monthly upon demand. Tenant agrees that Landlord
may file suit to recover any sums due to Landlord under this section from time
to time and that such suit or recovery of any amount due Landlord shall not be
any defense to any subsequent action brought for any amount not previously
reduced to judgment in favor of Landlord. If Landlord elects to terminate
Tenant's right to possession only without terminating this Lease, Landlord may,
at its option, enter into the Premises, remove Tenant's signs and other
evidences of tenancy, and take and hold possession thereof; provided, however,
that such entry and possession shall not terminate this Lease or release Tenant,
in whole or in part, from Tenant's obligation to pay the Rent reserved hereunder
for the full Term or from any other obligation of Tenant under this Lease.

C. Bankruptcy. In the event a petition is filed by or against Tenant seeking a
plan of reorganization or arrangement under the Federal Bankruptcy Code,
Landlord and Tenant agree, to the extent permitted by


                                       11
<PAGE>   11

law, that the trustee in bankruptcy shall determine within sixty (60) days after
commencement of the case, whether to assume or reject this Lease.

D. Attorneys' Fees. Tenant shall pay upon issuance of a final unappealable
judgment against Tenant all costs and expenses, including attorneys' fees paid
or incurred by Landlord in connection with any action or proceeding by Landlord
to terminate this Lease or to terminate Tenant's right to possession of the
Premises.

13. SURRENDER OF PREMISES. Upon the expiration or termination of this Lease or
termination of Tenant's right to possession of the Premises, Tenant shall
surrender and vacate the Premises immediately and deliver possession of the
Premises to Landlord in a clean, good and tenantable condition, ordinary wear
excepted; provided, however, that all alterations and improvements installed in
the Premises shall be promptly removed by Tenant (at Tenant's cost and expense)
at the termination or expiration of the Term if so requested by Landlord. Upon
any termination which occurs other than by reason of Tenant's default, Tenant
shall be entitled to remove from the Premises all moveable trade fixtures and
personal property of Tenant without credit or compensation from Landlord,
provided, Tenant shall immediately repair all damage to the Premises or the
Building resulting from such removal and shall restore the Premises to a
tenantable condition. In the event possession of the Premises is not immediately
delivered to Landlord or if Tenant shall fail to remove any moveable trade
fixtures or personal property which Tenant is entitled to remove, Landlord may
remove same without any liability to Tenant. Any moveable trade fixtures and
personal property which may be removed from the Premises by Tenant but which are
not so removed shall be conclusively presumed to have been abandoned by Tenant
and title to such property shall pass to Landlord without any payment or credit,
and Landlord may, at its option and at Tenant's expense, store and/or dispose of
such property.

14. HOLDING OVER.

A. Tenant shall pay Landlord double the Net Base Rent plus double the Rent
Adjustment then applicable for each month (or any part of a month) if Tenant
obtains Landlords written permission to retain possession month to month of all
or any part of the Premises after the expiration or termination of the Term of
this Lease. The provisions of this Paragraph 14 shall not constitute a waiver by
Landlord of any re-entry or eviction rights of Landlord available under this
Lease or by law.

B. Without limiting anything set forth in Paragraph 14A above, Tenant shall
indemnify, defend and forever hold harmless Landlord, the Beneficiary, the
Manager and their respective officers, partners and employees from and against
any and all claims, liabilities, actions, losses, damages and expenses
(including court costs and attorneys' fees) asserted against or sustained by any
such party and arising from or by reason of such retention of possession.

C. Reserved Parking. Notwithstanding the provision of section 3.A.(9) of this
Lease, the Landlord shall make available during the term of this lease a total
of ten (10) reserved parking spaces for the exclusive use of Security Associates
International, Inc.

15. OPTION TO RENEW.

A. So long as an event of default is not then existing the term of this Lease
may be extended, at the option of Tenant, for one additional period of five (5)
years with six (6) months or more prior written notice to Landlord with such
period being herein sometimes referred to as the Extended Term as follows:

B. The Extended Term shall be on the same terms, covenants and conditions of
this Lease and any reference herein to the "Terms" shall be deemed to include
any Extended Term applied thereto, except for the amount of Net Base Rent during
the Extended Term. The Net Base Rent during the first year of the Extended Term
shall be the same as the fifth year of the initial Lease Term. The Net Base Rent
for each succeeding year of the Extended Term shall be equal to one hundred five
percent (105%) of the annual Net Base Rent for the immediately preceding year.
Any termination of this Lease during the Initial Term of this Lease or an
Extended Term shall terminate all rights hereunder.

16. RULES AND REGULATIONS. Tenant shall abide by all reasonable rules and
regulations adopted by Landlord from time to time for the operation and
management of the Building. If any rules and regulations are contrary to the
provisions of this Lease, the provisions of this Lease shall govern. Attached to
this Lease as Exhibit "C" are the current rules and regulations for the
Building, all of which Tenant


                                       12
<PAGE>   12

hereby agrees shall be deemed to be reasonable. Landlord shall not be
responsible for the violation of any rules or regulations of the Building by
other tenants of the Building.

17. FIRE AND OTHER CASUALTY. If all or a substantial part of the Premises are
rendered untenantable by reason of fire or other casualty, or if the Building is
damaged by fire or other casualty in such a manner as materially adversely
affects access to or use of the Premises, Landlord shall with reasonable
diligence take such action as is necessary to repair and restore the Premises
and the Building. In the event Landlord fails for any reason to complete said
restoration within ninety (90) days then either party shall have the right to
terminate this Lease by giving to the other party written notice of such
election within ten (10) days after receipt of the architect's certificate. If
said fire or other casualty results in the total destruction of the Building,
this Lease shall automatically terminate as of the date of said fire or other
casualty. Net Base Rent and Rent Adjustment shall abate for that part of the
Premises which are untenantable on a per diem and proportionate area basis from
the date of the fire or other casualty until Landlord has substantially
completed the repair and restoration work; provided, that Tenant does not occupy
or use such part of the Premises which are untenantable during such period.

18. TENANT'S INSURANCE. Tenant, at its expense, shall maintain in force at all
times during the Term and comprehensive general public liability insurance,
which shall include coverage for personal liability, contractual liability,
tenant's legal liability, bodily injury, death and property damage, all on an
occurrence basis with respect to the business carried on in or from the Premises
and Tenant's use and occupancy of the Premises, with coverage for any one
occurrence or claim of not less than two million dollars ($2,000,000), which
insurance shall include Landlord and Beneficiary as named insured and shall
protect Landlord and Beneficiary in respect of claims by Tenant as if Landlord
and Beneficiary were separately insured. Such insurance shall be on terms and
with insurers reasonably acceptable to Landlord. Any casualty insurance carried
by Tenant and covering the Premises or Tenant's fixtures, property or equipment
located in the Premises shall contain a waiver by the insurer of any rights of
subrogation or indemnity or any other claim to which the insurer might otherwise
be entitled against Landlord, the Beneficiary, the Manager and their respective
partners, agents or employees. Tenant shall furnish to Landlord prior to the
Commencement Date, certificates or other evidences acceptable to Landlord as to
the insurance from time to time maintained by Tenant and, no later than thirty
(30) days prior to the date such insurance otherwise would expire, Tenant shall
furnish Landlord with certificates confirming the renewal or continuation of
such insurance for themselves and all others claiming under them, including the
insurer, waive all rights including rights of subrogation against the other for
loss, damage or liability resulting from a risk which is insured against by
either party, to the extent of any recovery collectible under such insurance;
provided, however, that this waiver shall apply only when permitted by the
applicable policy of insurance.

19. WAIVER OF RECOVERS AND SUBROGATION. Notwithstanding any other provision of
this Lease to the contrary, Lessor and Lessee agree that in the event that the
building of which the Premises are a part or any part or parts thereof or the
fixtures, merchandise, and contents therein are damaged or destroyed by fire or
other casualty, each of the parties hereto, for itself and any person or entity
claiming through or under such party by way of subrogation or otherwise, hereby
waives all rights of recovery from the other party hereto for any loss or damage
whether caused by such other parties negligence or otherwise. Lessor shall cause
each insurance policy carried by Lessor insuring the building of which the
Premises are a part or any part or parts thereof against loss by fire or any
other casualties covered or embraced by all risk or special form property
casualty insurance to be written in such a manner so as to provide that the
insurer waives all right of recovery by way of subrogation against Lessee in
connection with any loss or damage covered by the policy or policies and that
such waiver shall not invalidate such insurance policy or policies. Lessee will
cause each Insurance policy carried by Lessee insuring Lessee's property in the
Premises to be written in such a manner so as to provide that the insurer waives
all right of recovery by way of subrogation against Lessor in connection with
any loss or damage covered by the policy and that such waiver shall not
invalidate such insurance policy or policies.

20. LANDLORD'S RIGHTS. Landlord shall have the following rights exercisable
without notice (except as expressly provided to the contrary) and without being
deemed an eviction or disturbance of Tenant's use or possession of the Premises
or giving rise to any claim for set-off or abatement of Rent: (1) To change the
name or street address of the Building upon prior written notice to Tenant; (2)
To install, affix and maintain all signs on the exterior and/or interior of the
Building; (3) To designate and/or approve prior to installation, all types of
signs, window shades, blinds, drapes, awnings or other similar items, and all
internal lighting that may be visible from the exterior of the Premises; (4) To
display the Premises to holders of mortgages or trust deeds encumbering the
Building or potential purchasers of the Building at any


                                       13
<PAGE>   13

reasonable hour, and to prospective tenants at reasonable hours during the last
twelve (12) months of the Term; (5) a notice of not less than forty eight (48)
hours shall be provided prior to changing the arrangement of entrances, doors,
corridors, and stairs in or outside of the Building; (6) To grant to any party
the exclusive right to conduct any business or render any service in or to the
Building, provided such exclusive right shall not operate to prohibit Tenant
from using the Premises for the purposes permitted under this Lease; (7) To
prohibit the placing of vending or dispensing machines of any kind in or about
the Premises other than for use by Tenant's employees; (8) To have access for
Landlord and other tenants of the Building to any mail chutes and boxes located
in or on the Premises according to the rules of the United States Post Office
and to discontinue any mail chute service in the Building; (9) To close the
Building after normal business hours, except that Tenant and its employees and
invitees shall be entitled to admission at all times under such regulations as
Landlord prescribes for security purposes; (10) To take any and all reasonable
measures, including inspections and repairs to the Premises or to the Building,
as may be necessary or desirable in the operation or protection of the Building;
(11) To retain at all times master keys or pass keys to the Premises; (12) To
install, operate and maintain security systems which monitor, by closed circuit
television or otherwise, all persons entering and leaving the Building; (13) To
install and maintain pipes, ducts, conduits, wires and structural elements
located in the Premises which serve other parts or other tenants of the
Building; (14) To make alterations, improvements, repairs and replacements to
the Building or any systems, equipment, machinery or common areas located in,
on, under or outside of the Building; and (15) To install blinds and/or window
treatments in the Premises in order to maintain conformance with the standards
or aesthetics of the Building.

21. ESTOPPEL CERTIFICATE. Tenant shall within five (10) business days after each
prior written request from Landlord, execute and deliver in form and substance
satisfactory to Landlord, an estoppel letter signed by an officer or partner of
Tenant and certifying: the Commencement Date and the Expiration Date; the date
to which Net Base Rent and Rent Adjustment has been paid; the amount of Net Base
Rent and Rent Adjustment then being paid; the amount of any security deposit;
that Tenant has accepted the Premises; that this Lease is in full force and
effect and has not been modified, amended or assigned (or, if modified, stating
the nature of such modification and certifying that this Lease, as so modified,
is in full force and effect); that all improvements have been fully completed;
that there are no defaults of Landlord under this Lease nor any existing
condition upon which the giving of notice or lapse of time would constitute a
default; that Tenant has not received any concession; that there are no offsets
to the payment of Rent; that Tenant has received no notice from any insurance
company of any defects or inadequacies of the Premises; Tenant has no options or
rights other than as set forth in this Lease; or by operation of law and such
other matters which Landlord may reasonably request. If the letter is to be
delivered to a purchaser or other subsequent owner of the Building, it shall
further include the agreement of Tenant to recognize such purchaser or other
subsequent owner as Landlord under this Lease and to pay Rent to the purchaser
or other subsequent owner or its designee in accordance with the terms of this
Lease. It is expressly understood and agreed that any such statement may be
relied upon by any prospective purchaser, mortgagee or ground lessor of all or
any portion of the Real Estate. Tenant's failure to deliver such statement
within said five (5) day period shall be conclusive upon Tenant that this Lease
is in full force and effect, without modification except as may be represented
by Landlord, that there are no uncured defaults in Landlord's performance, that
not more than two (2) months' rental has been paid in advance and that all other
statements required to be made in the estoppel letter are conclusively made.

22. MORTGAGE BY LANDLORD. This Lease is expressly subject and subordinate at all
times to (1) any ground, underlying or operating lease of the Building or the
Land now or hereafter existing and all amendments, renewals and modifications to
any such lease, and (2) the lien of any now existing or hereafter created
mortgage or trust deed encumbering fee title to the Building, the Land and/or
the leasehold estate under any such ground, underlying or operating lease, and
to all advances made or to be made upon the security of such lien. Tenant
agrees:

(a) if requested by any mortgagee, trustee or lessor, Tenant shall subordinate
its interest in this Lease to any such mortgage, trust deed or lease and will
execute such subordination agreement or agreements as may be reasonably required
by any said mortgagee, trustee or lessor, and

(b) in the event of any default by Landlord under this Lease which would give
Tenant the right to terminate this Lease or to claim a partial or total
eviction, Tenant will not exercise any such right until (i) it has notified in
writing the mortgagee, holder of such trust deed or lessor, as the case may be
(if the name and address of such mortgagee, holder or lessor shall have
previously been furnished by written notice to Tenant) of such default, and (ii)
such mortgagee, holder or


                                       14
<PAGE>   14

lessor, as the case may be, fails within a reasonable time (not to exceed thirty
(30) days) after receipt of such notice to cause such default to be cured, and

(c) if any such mortgage or trust deed be foreclosed (or a deed given in lieu of
foreclosure), or if any such lease be terminated, upon request of the mortgagee,
holder or lessor, as the case may be, Tenant will attorn to the purchaser at
foreclosure sale (or grantee of deed in lieu of foreclosure) or the lessor under
the lease, as the case may be, and will execute such instruments as may be
necessary or appropriate to evidence such attornment.

23. NOTICES. All notices and approvals to be given by one party to the other
party under this Lease shall be given in writing, mailed or delivered as
follows:

(a) To Landlord, LaSalle Bank National Association, Successor Trustee to
American National Bank and Trust Company of Chicago, As Trustee Under Trust No.
59948, 135 So. LaSalle Street, Suite 2500, Chicago IL 60603.


(b) Washington Square Capital, 100 Washington Square, Suite 800, Minneapolis, MN
55441-2147, Attn: Ms. Janine Desplinter.

(c) Liz-Green, Inc., 2101 So. Arlington Heights Road, Arlington Heights,
Illinois 60005, Attention: Property Manager or to such other person or persons
or at such other address of addresses designated by notice to Tenant.

(d) To Tenant at the location stated in Paragraph 1C until Tenant takes
possession of the Premises and then at the Premises.

Notices shall be delivered by hand or by United States certified or registered
mail, postage prepaid, return receipt requested. Notices shall be considered to
have been given upon personal delivery or upon posting in the United States
Mails.

24. MISCELLANEOUS.

A. Binding Effect. This Lease shall be binding upon and inure to the benefit of
Landlord and Tenant and their respective heirs, legal representatives,
successors and permitted assigns.

B. Default Interest. All amounts owing to Landlord under this Lease for which
the date of payment is not expressly fixed, shall be paid within thirty (30)
days after the date Landlord renders statements of account. Tenant shall pay
Landlord interest from the date payment is due until it is made on any Rent
owing under this Lease, which is not paid with in ten (thirty (30) of the date
it first becomes due and on all other amounts not paid Landlord within thirty
(30) days after they become due, at a rate equal to the sum of three percent
(3%), plus the prime rate of interest from time to time announced by LaSalle
Bank National Association.

C. Eminent Domain. In the event that all or a substantial part of the Premises
or the Building are taken by eminent domain (or by a deed given in lieu of
condemnation) so that the Premises cannot be reasonably used by Tenant for the
purposes for which they are leased, then either party may terminate this Lease
by giving written notice of termination to the other party within thirty (30)
days after such taking. In the event of any taking by eminent domain (or deed
given in lieu of condemnation) the entire award shall be paid to and retained by
Landlord. Subject to the foregoing, Tenant may pursue a separate award against
the condemning authority in a separate proceeding for Tenant's loss, if any, to
leasehold improvements paid for by Tenant without any credit or allowance from
Landlord and for Tenant's moving and relocation expenses.

D. Exhibits. All Exhibits attached to this Lease are made a part of this Lease
and incorporated by this reference into this Lease.


                                       15
<PAGE>   15

E. Entire Agreement. This Lease and the Exhibits and Rider (if any) attached to
this Lease set forth all the covenants, promises, assurances, agreements,
representations, conditions, warranties, statements and understandings (the
"Representations" collectively) between Landlord and Tenant concerning the
Premises and the Building, and there are no Representations, either oral or
written, between them other than those in this Lease. This Lease supersedes and
revokes all previous negotiations, estimates of the initial and/or future
amounts of Expenses, Taxes and/or Rent, arrangements, letters of intent, offers
to lease, reservations of space, lease proposals, brochures, Representations and
information conveyed, whether oral or in writing, between the parties or their
respective representatives, agents, brokers, salespersons or any other person
purporting to represent Landlord or Tenant. Tenant acknowledges that it has not
been induced to enter into this Lease by any Representations not set forth in
this Lease, it has not relied on any such Representations, no such
Representation shall be used in the interpretation or construction of this Lease
and Landlord shall have no liability for any consequences arising as a result of
any such Representations. No subsequent alteration, amendment, change or
addition to this Lease shall be binding upon Landlord or Tenant unless in
writing signed by both parties.

F. Signing. The signing of this Lease by Tenant and delivery of this Lease to
Landlord or its agent does not constitute a reservation of or option for the
Premises or an agreement to enter into a Lease and this Lease shall become
effective only if and when Landlord signs and delivers same to Tenant; provided,
however, the signing and delivery by Tenant of this Lease to Landlord or its
agent shall constitute an irrevocable offer by Tenant to lease the Premises on
the terms and conditions contained in this Lease, which offer may not be
withdrawn or revoked for thirty (30) days after such signing and delivery. If
Tenant is a corporation, it shall deliver to Land-lord concurrently with the
delivery to Landlord of a signed Lease, certified resolutions of Tenant's
directors authorizing the signing and delivery of this Lease and the performance
by Tenant of its obligations under this Lease.

G. No Accord. No payment by Tenant or receipt by Landlord of a lesser amount
than any installment or payment of Rent due shall be deemed to be other than on
account of the amount due, and no endorsement or statement on any check or any
letter accompanying any check or payment of Rent shall be considered an accord
and satisfaction, and Landlord may accept such check or payment without
prejudice to Landlord's right to recover the balance of such installment or
payment of Rent or pursue any other remedies available to Landlord. No receipt
of money by Landlord from Tenant after the termination of this Lease or Tenant's
right to possession of the Premises shall reinstate, continue or extend the
Term.

H. Broker. Tenant represents to Landlord and the Beneficiary that except for the
broker stated in Paragraph 1(0), Tenant has not dealt with any real estate
broker, sales person, or finder in connection with this Lease, and no such
person initiated or participated in the negotiation of this Lease, or showed the
Premises to Tenant. Tenant agrees to indemnify, defend and hold harmless
Landlord, the Beneficiary, the Manager and their respective officers, partners
and employees, from and against any and all claims, demands, for brokerage
commissions or fees arising out of a breach of such representation. Unless
otherwise agreed by the parties, Landlord shall be responsible for the payment
of all commissions to the broker stated in Paragraph 1(0), based upon the
leasing commission policy of Landlord applicable to the Building and in effect
as of the date of this Lease.

I. Force Majeure. Landlord shall not be considered in default of any of the
terms, covenants and conditions of this Lease on Landlord's part to be
performed, if Landlord fails to timely perform same and such failure is due to
in whole or in part to any strike, lockout, labor trouble (whether legal or
illegal), civil disorder, inability to procure materials, failure of power or
reduction or interruption in the furnishing or level of power, water, sewer, gas
or any other service or utility to be furnished or provided under this Lease,
restrictive governmental laws and regulations, riots, insurrections, war, fuel
shortages, accidents, casualties, Acts of God, acts caused directly or
indirectly by Tenant (or Tenant's agents, employees or invitees) or any other
cause beyond the reasonable control of Landlord.

J. Paragraphs. Paragraph captions in this Lease are inserted only as a matter of
convenience and in no way define, limit, construe or describe the scope or
intent of such Paragraphs.

K. Applicable Law. This Lease shall be construed in accordance with the laws of
the State of Illinois.

L. Time. Time is of the essence of this Lease and the performance of all
obligations under this Lease.


                                       16
<PAGE>   16

M. Landlord's Performance. If Tenant fails timely to perform any of its duties
under this Lease, Landlord shall have the right (but not the obligation) after
the expiration of any applicable notice and cure period, to itself perform such
duty on behalf and at the expense of Tenant, without further notice to Tenant,
and all sums incurred by Landlord in performing such duty shall be considered
additional rent under this Lease and shall be due and payable upon demand by
Landlord.

N. Recording. Tenant shall not record this Lease or a memorandum of this Lease
in the Office of the Recorder of Deeds of Cook County, Illinois.

O. Severability. If any clause, phrase, provision or portion of this Lease or
the application of same to any person or circumstance shall be invalid or
unenforceable under applicable law, such event shall not affect, impair or
render invalid or unenforceable the remainder of this Lease, nor any other
clause, phrase, provision or portion of this Lease, nor shall it affect the
application of any clause, phrase, provision or portion of this Lease to other
persons or circumstances.

P. Litigation Costs . In the event any litigation is instituted by any party to
this Agreement against the other party regarding the construction of any term or
to recover any damages resulting from a breach of any term of this Agreement,
the prevailing party in any such action shall be entitled to recover from the
losing party all of such prevailing party's attorneys' fees and costs associated
with such action.

25. EXCULPATION. This Lease is executed by LaSalle Bank National Association,
Successor Trustee to American National Bank and Trust Company of Chicago, As
Trustee Under Trust No. 59948, not personally but as Trustee as aforesaid, in
the exercise of the power and authority conferred upon and vested in it as such
Trustee, and under the express direction of the beneficiaries of a certain Trust
Agreement dated December 15, 1983, and known as Trust Number 59948 at LaSalle
Bank National Association, to all provisions of which Trust Agreement this Lease
is expressly made subject. It is expressly understood and agreed that nothing
contained in this Lease shall be construed as creating any liability whatsoever
against said Trustee personally, and in particular without limiting the
generality of the foregoing, there shall be no personal liability to pay any
indebtedness accruing under this Lease or to perform any covenant, either
express or implied, contained in this Lease, or to keep, preserve or sequester
any property of said Trust, and that all personal liability of said Trustee of
every sort, if any, is hereby expressly waived by Tenant, and by every person
now or hereafter claiming any right or security under this Lease; and that so
far as the said Trustee is concerned the owner of any indebtedness or liability
accruing under this Lease shall look solely to the Premises for the payment of
same. It is further understood and agreed that the said Trustee has no agents or
employees and merely holds naked legal title to the Real Estate; that said
Trustee has no control over and under this Lease, assumes no responsibility for,
(1) the management or control of the Real Estate, (2) the upkeep, inspection,
maintenance or repair of the Real Estate, (3) the collection of rents, or the
rental of the Real Estate, or (4) the conduct of any business which is carried
on upon the Real Estate.


                                       17
<PAGE>   17

IN WITNESS WHEREOF, this Lease is executed as of the day and year aforesaid.


TENANT:   By:                                            Date:
             ------------------------------------------       ------------------
                James S. Brannen, President
                Security Associates International, Inc.




LANDLORD: LASALLE BANK NATIONAL ASSOCIATION, SUCCESSOR TRUSTEE TO AMERICAN
          NATIONAL BANK AND TRUST COMPANY OF CHICAGO, NOT PERSONALLY BUT SOLELY
          AS TRUSTEE UNDER IT'S TRUST NO. 59948

          By:                                            Date:
             ------------------------------------------       ------------------

                                       18
<PAGE>   18

EXHIBIT "A", TO LEASE DATED AUGUST 12, 2000, BY AND BETWEEN LASALLE NATIONAL
ASSOCIATION SUCCESSOR TRUSTEE TO AMERICAN NATIONAL BANK AND TRUST COMPANY UNDER
TRUST AGREEMENT KNOWN AS TRUST NO. 59948 AS LANDLORD AND SECURITY ASSOCIATES
INTERNATIONAL, INC., AS TENANT.

<TABLE>
<CAPTION>
                                                                   Total
                      Net Base Rent        Tax And Operating      Estimated
                         Actual            Expenses Estimated     Payments
                      -------------        ------------------     ---------
<S>                   <C>                  <C>                    <C>
    1 /1/2001           18,460.00              14,191.35          32,651.35
    2 /1/2001           18,460.00              14,191.35          32,651.35
    3 /1/2001           18,460.00              14,191.35          32,651.35
    4 /1/2001           18,460.00              14,191.35          32,651.35
    5 /1/2001           18,460.00              14,191.35          32,651.35
    6 /1/2001           18,460.00              14,191.35          32,651.35
    7 /1/2001           18,460.00              14,191.35          32,651.35
    8 /1/2001           18,460.00              14,191.35          32,651.35
    9 /1/2001           18,460.00              14,191.35          32,651.35
   10 /1/2001           18,460.00              14,191.35          32,651.35
   11 /1/2001           18,460.00              14,191.35          32,651.35
   12 /1/2001           18,460.00              14,191.35          32,651.35
    1 /1/2002           19,106.10              14,759.00          33,865.10
    2 /1/2002           19,106.10              14,759.00          33,865.10
    3 /1/2002           19,106.10              14,759.00          33,865.10
    4 /1/2002           19,106.10              14,759.00          33,865.10
    5 /1/2002           19,106.10              14,759.00          33,865.10
    6 /1/2002           19,106.10              14,759.00          33,865.10
    7 /1/2002           19,106.10              14,759.00          33,865.10
    8 /1/2002           19,106.10              14,759.00          33,865.10
    9 /1/2002           19,106.10              14,759.00          33,865.10
   10 /1/2002           19,106.10              14,759.00          33,865.10
   11 /1/2002           19,106.10              14,759.00          33,865.10
   12 /1/2002           19,106.10              14,759.00          33,865.10
    1 /1/2003           19,774.81              15,201.77          34,976.59
    2 /1/2003           19,774.81              15,201.77          34,976.59
    3 /1/2003           19,774.81              15,201.77          34,976.59
    4 /1/2003           19,774.81              15,201.77          34,976.59
    5 /1/2003           19,774.81              15,201.77          34,976.59
    6 /1/2003           19,774.81              15,201.77          34,976.59
    7 /1/2003           19,774.81              15,201.77          34,976.59
    8 /1/2003           19,774.81              15,201.77          34,976.59
    9 /1/2003           19,774.81              15,201.77          34,976.59
   10 /1/2003           19,774.81              15,201.77          34,976.59
   11 /1/2003           19,774.81              15,201.77          34,976.59
   12 /1/2003           19,774.81              15,201.77          34,976.59
    1 /1/2004           20,466.93              15,657.83          36,124.76
    2 /1/2004           20,466.93              15,657.83          36,124.76
    3 /1/2004           20,466.93              15,657.83          36,124.76
    4 /1/2004           20,466.93              15,657.83          36,124.76
    5 /1/2004           20,466.93              15,657.83          36,124.76
    6 /1/2004           20,466.93              15,657.83          36,124.76
</TABLE>



                                       19

<PAGE>   19

<TABLE>
<CAPTION>
                                                                  Total
                     Net Base Rent        Tax And Operating      Estimated
                        Actual            Expenses Estimated     Payments
                     -------------        ------------------     ---------
<S>                   <C>                  <C>                    <C>
    7/1/2004           20,466.93              15,657.83          36,124.76
    8/1/2004           20,466.93              15,657.83          36,124.76
    9/1/2004           20,466.93              15,657.83          36,124.76
   10/1/2004           20,466.93              15,657.83          36,124.76
   11/1/2004           20,466.93              15,657.83          36,124.76
   12/1/2004           20,466.93              15,657.83          36,124.76
    1/1/2005           21,183.27              16,127.56          37,310.84
    2/1/2005           21,183.27              16,127.56          37,310.84
    3/1/2005           21,183.27              16,127.56          37,310.84
    4/1/2005           21,183.27              16,127.56          37,310.84
    5/1/2005           21,183.27              16,127.56          37,310.84
    6/1/2005           21,183.27              16,127.56          37,310.84
    7/1/2005           21,183.27              16,127.56          37,310.84
    8/1/2005           21,183.27              16,127.56          37,310.84
    9/1/2005           21,183.27              16,127.56          37,310.84
   10/1/2005           21,183.27              16,127.56          37,310.84
   11/1/2005           21,183.27              16,127.56          37,310.84
   12/1/2005           21,183.27              16,127.56          37,310.84
    1/1/2006           21,924.69              16,611.39          38,536.08
    2/1/2006           21,924.69              16,611.39          38,536.08
    3/1/2006           21,924.69              16,611.39          38,536.08
    4/1/2006           21,924.69              16,611.39          38,536.08
    5/1/2006           21,924.69              16,611.39          38,536.08
    6/1/2006           21,924.69              16,611.39          38,536.08
    7/1/2006           21,924.69              16,611.39          38,536.08
    8/1/2006           21,924.69              16,611.39          38,536.08
    9/1/2006           21,924.69              16,611.39          38,536.08
   10/1/2006           21,924.69              16,611.39          38,536.08
   11/1/2006           21,924.69              16,611.39          38,536.08
   12/1/2006           21,924.69              16,611.39          38,536.08
    1/1/2007           22,692.05              17,275.84          39,967.90
    2/1/2007           22,692.05              17,275.84          39,967.90
    3/1/2007           22,692.05              17,275.84          39,967.90
    4/1/2007           22,692.05              17,275.84          39,967.90
    5/1/2007           22,692.05              17,275.84          39,967.90
    6/1/2007           22,692.05              17,275.84          39,967.90
    7/1/2007           22,692.05              17,275.84          39,967.90
    8/1/2007           22,692.05              17,275.84          39,967.90
    9/1/2007           22,692.05              17,275.84          39,967.90
   10/1/2007           22,692.05              17,275.84          39,967.90
   11/1/2007           22,692.05              17,275.84          39,967.90
   12/1/2007           22,692.05              17,275.84          39,967.90
    1/1/2008           23,486.28              17,794.12          41,280.40
    2/1/2008           23,486.28              17,794.12          41,280.40
    3/1/2008           23,486.28              17,794.12          41,280.40
    4/1/2008           23,486.28              17,794.12          41,280.40
    5/1/2008           23,486.28              17,794.12          41,280.40
    6/1/2008           23,486.28              17,794.12          41,280.40
    7/1/2008           23,486.28              17,794.12          41,280.40
    8/1/2008           23,486.28              17,794.12          41,280.40
    9/1/2008           23,486.28              17,794.12          41,280.40
   10/1/2008           23,486.28              17,794.12          41,280.40
</TABLE>



                                       20

<PAGE>   20

<TABLE>
<CAPTION>
                                                                  Total
                     Net Base Rent        Tax And Operating      Estimated
                        Actual            Expenses Estimated     Payments
                     -------------        ------------------     ---------
<S>                   <C>                  <C>                    <C>
   11/1/2008           23,486.28              17,794.12          41,280.40
   12/1/2008           23,486.28              17,794.12          41,280.40
    1/1/2009           24,308.29              18,327.94          42,636.24
    2/1/2009           24,308.29              18,327.94          42,636.24
    3/1/2009           24,308.29              18,327.94          42,636.24
    4/1/2009           24,308.29              18,327.94          42,636.24
    5/1/2009           24,308.29              18,327.94          42,636.24
    6/1/2009           24,308.29              18,327.94          42,636.24
    7/1/2009           24,308.29              18,327.94          42,636.24
    8/1/2009           24,308.29              18,327.94          42,636.24
    9/1/2009           24,308.29              18,327.94          42,636.24
   10/1/2009           24,308.29              18,327.94          42,636.24
   11/1/2009           24,308.29              18,327.94          42,636.24
   12/1/2009           24,308.29              18,327.94          42,636.24
    1/1/2010           25,159.09              18,877.78          44,036.87
    2/1/2010           25,159.09              18,877.78          44,036.87
    3/1/2010           25,159.09              18,877.78          44,036.87
    4/1/2010           25,159.09              18,877.78          44,036.87
    5/1/2010           25,159.09              18,877.78          44,036.87
    6/1/2010           25,159.09              18,877.78          44,036.87
    7/1/2010           25,159.09              18,877.78          44,036.87
    8/1/2010           25,159.09              18,877.78          44,036.87
    9/1/2010           25,159.09              18,877.78          44,036.87
   10/1/2010           25,159.09              18,877.78          44,036.87
   11/1/2010           25,159.09              18,877.78          44,036.87
   12/1/2010           25,159.09              18,877.78          44,036.87
</TABLE>



                                       21