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                                                                   EXHIBIT 10.48


                            SECOND AMENDMENT TO LEASE


         THIS SECOND AMENDMENT TO LEASE, effective January 1, 1999, by and
between 1471 Building Corporation ("Lessor") and Security Associates
International, Inc., a Delaware corporation ("Lessee") modifies and extends that
certain lease of the premises commonly known as 1471 S.W. 12th Avenue, Pompano
Beach, Florida 33069 (the "Leased Premises") as follows:

         WHEREAS, the sublease dated December 29, 1996 by and between William
Jackson and Elizabeth Jackson and Lessee (the "Sublease") was amended by a First
Amendment to Lease (the "First Amendment") executed on or about January 7, 1997
(the sublease as so amended is referred to as the "Lease"); and

         WHEREAS, Lessor and Lessee have agreed to further amend the Lease as
set forth below.

         NOW, THEREFORE, in consideration of the premises and the mutual
promises contained herein and in the Lease, the parties agree as follows:

         1.   Section 1.04 of the Lease is amended to read in its entirety as
              follows: "Property: The entire building located at 1471 S.W. 12th
              Avenue, Pompano Beach, Florida consisting of approximately 13,000
              square feet; provided, however, that until September 1, 1999 the
              Property shall not include the approximately 900 square feet being
              leased to The Steritech Group, Inc.

         2.   Section 1.05 of the Lease is amended to provide that the term of
              the Lease is extended December 31, 2003.

         3.   Section 1.13 is amended to provide that commencing January 1, 1999
              Rent shall be $13,750 per month, plus applicable Florida sales
              tax, payable in advance, provided, however, until September 1,
              1999, the monthly rental shall be $12,850 per month.

         4.   Section 1.15 is amended so that (i) Lessee's option to extend the
              term of the Lease for an additional five (5) years shall be for
              the renewal period commencing January 1, 2004, provided that
              Lessee gives written notice of its intention to extend no later
              than six (6) months before the end of the term. All other
              provisions of Section 1.15 shall remain in effect.

         5.   Section 3.01 is amended to provide that for a calendar year 1999,
              Lessee's monthly payment for real estate taxes shall be $1,661 per
              month and payments for property and casualty insurance and
              maintenance fees shall be $525 per month, provided, however, that
              until September 1, 1999, such payments shall be $1,395.24 and $441
              per month, respectively. The provisions of Section 3.01 providing
              for annual adjustments to the
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              amounts payable by Lessee by reason of increase in real estate
              taxes, insurance and maintenance fees shall remain in full force
              and effect, but only with respect to increases beyond the amounts
              assessed for calendar year 1999.

         6.   Paragraph 2 of the First Amendment (Utilities/Services) shall be
              of no further effect. In its place Section 3.02 of the Sublease
              shall be the effective provision governing the Lease, as of
              January 1,1999, with the following modifications: The last
              sentence of Section 3.02 shall read in its entirety as follows:
              "Lessee shall supply sewer service and such refuse disposal and
              water as is reasonably incident to Lessee's occupancy."

         7.   Section 5.03 is amended by replacing the first sentence of that
              section with the following: "The Lessor, at the expense of the
              Lessor, will keep the roof and the foundation of the Building in
              good and serviceable condition and repair; provided, however, that
              if the roof or foundation of said Building shall become in need of
              repair, it shall be the duty of the Lessee to notify the Lessor of
              such needed repair. The balance of Section 5.03 shall remain in
              full force and effect.

         IN WITNESS WHEREOF, Lessor and Lessee have executed this Second
Amendment to Lease, effective as of the day and year first written above.

         LESSOR:

         1471 BUILDING CORPORATION


         By:
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         Its:
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         LESSEE:

         SECURITY ASSOCIATES INTERNATIONAL, INC.


         By: /s/ DANIEL ZITTNO
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         Its: CFO
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