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                            SECOND AMENDMENT TO LEASE


This Second Amendment to Lease (hereinafter referred to as "Amendment-1") is
entered into by and between AMERICAN NATIONAL BANK and TRUST COMPANY OF CHICAGO,
not personally but solely as Trustee under Trust No. 59948 (hereinafter referred
to as "Landlord") and Security Associates International, Inc., (hereinafter
referred to as "Tenant").

A. Whereas, Landlord and Tenant entered into a lease dated November 21, 1995,
(hereinafter referred to as the "Lease"), covering certain premises known as
Suite 100 occupying approximately 4,520 rentable square feet located at 2101
South Arlington Heights Road, Arlington Heights, Illinois 60005 (the
"Building"), and First Amendment to Lease dated December 9, 1996 (hereinafter
referred to as the "Amendment"), covering certain premises known as Suite 110
occupying approximately 2,561 rentable square feet located at the Building, as
more fully described in said Lease.

B. Whereas, Landlord and Tenant now desire to amend the Lease and the Amendment
and also to lease an additional 2,242 rentable square feet located at the
Building and known as Suite 111 at a rental and upon all the other terms,
covenants and conditions as hereinafter set forth, but not otherwise.

Now therefore, in consideration of the mutual covenants and conditions herein
contained and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

1. Length of Term. The new lease term for Suite 111 shall commence on January 1,
1998 for five (5) years and shall terminate on December 31, 2002. The new lease
term for Suite 100 shall commence on January 1, 1998 for five (5) years and
shall terminate on December 31, 2002. The new lease term for Suite 110 shall
commence on January 1, 1998 for five (5) years and shall terminate on December
31, 2002. The new term shall remain in full force and effect without
interruption for five (5) years except if an event of default occurs.

2. Net Base Rent. The Net Base Rent is listed out on the attached Exhibit "G"
broken down by month. The annual Net Base Rent payments for Suite 100, Suite 110
and Suite 111 are as follows:

                  Year 1                             $108,240.12
                  Year 2                             $108,240.12
                  Year 3                             $108,240.12
                  Year 4                             $111,487.32
                  Year 5                             $114,831.94

3. Security Deposit. When Tenant signs this Amendment-1, then Tenant shall pay
to Landlord the sum of $2,169.14 as security for the performance of it's
obligations under this Amendment-1.

4. Operating Expenses. The Building's Annual Operating Expenses shall be paid in
addition to and apart from the Net Base Rent. These expenses shall be billed as
additional rent in the form of monthly progress payments based upon an occupancy
percentage of 15.102%.

5. Real Estate Taxes. The Building's Real Estate Taxes shall be paid in addition
to and apart from the Net Base Rent. These expenses shall be billed as
additional rent in the form of monthly progress payments based upon an occupancy
percentage of 15.102%.

6.  Tenant Improvements. All construction costs to remodel Suite 111 shall be
borne by the Landlord. The scope of work for these tenant improvements are
listed out on the attached Exhibit "H."



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7.  Payment of Rent. All rent due under the Lease and this Amendment-1, shall be
paid to: Arlington Associates, c/o Liz-Green, Inc. as the Managing Agent, (the
"Manager"). Checks or other form of payment shall be mailed or delivered to the
following address:

                                  Liz-Green, Inc.
                                  Suite 115
                                  2101 South Arlington Heights Road
                                  Arlington Heights, Illinois 60005-4142

8.  Broker. Tenant and Landlord represent and warrant to each other that they
have not dealt with any broker or finder in connection with this Second
Amendment to Lease other than Liz-Green, Inc., "Broker". Landlord hereby agrees
to be responsible for and pay any and all brokerage commissions, fees or claims
of any kind owing to Broker in connection with this Amendment-1, and shall
indemnify and hold Tenant harmless from any and all claims, costs, expenses
(including court costs and reasonable legal fees) incurred by Tenant in
connection therewith. Tenant agrees to indemnify and hold Landlord harmless from
and against any claims, costs, expenses (including court costs and reasonable
legal fees) and other liabilities incurred by Landlord by reason of any claim or
action for a commission or other compensation by any other broker or finder, if
any, with which Tenant has dealt with respect to this Amendment-1. Landlord
shall have no liability for any brokerage commissions arising from a sublease or
assignment by Tenant. The provisions of this paragraph shall survive the
expiration or sooner termination of this Second Amendment to Lease.

9.  No Other Changes. Except as and to the extent expressly provided for in this
Second Amendment to Lease, the Lease shall remain in full force and effect and
shall be applicable according to all of its terms to Suite 100, Suite 110 and
Suite 111.

10. Entire Agreement. This Amendment-1 constitutes the entire understanding of
the parties regarding this Second Amendment to Lease. There are no promises,
representations or understandings, other than as set forth in these documents.

    IN WITNESS WHEREOF, this Amendment to Lease is executed as of December 10,
1997.

    TENANT:       Security Associates International, Inc.



    By:   /s/ James S. Brannen
       ---------------------------------
          James S. Brannen, President

    Date:  12/11/97
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    LANDLORD:  AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO, not 
               personally but solely as Trustee under its Trust No. 59948


    By:      /s/ David Rosenfield
       ---------------------------------
    Title:   AVP
          ------------------------------