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                                                                   Exhibit 10.10

             COST AND EXPENSE SHARING AND REIMBURSEMENT AGREEMENT
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     THIS COST AND EXPENSE SHARING AND REIMBURSEMENT AGREEMENT (this
"Agreement") is effective as of the 31st day of August, 1999, by and between
PINNACLE TOWERS INC., a Delaware corporation ("PTI") and Pinnacle Towers III
Inc., a Florida corporation  ("PT3").

     WHEREAS, PT3 owns certain assets which it acquired from PTI; and

     WHEREAS, in connection with the conduct of its business, PT3 considers it
necessary or convenient to avail itself of certain of PTI's personnel,
facilities and general and administrative overhead, and PTI is willing to make
such available to PT3; and

     WHEREAS, PT3 has agreed to reimburse PTI for its allocable share of the
cost and expense of such shared personnel, facilities and general and
administrative overhead as determined in the manner hereinafter provided;

     NOW, THEREFORE, in consideration of the representations, warranties,
covenants and agreements herein contained, the parties agree as follows:

     1.   Provision of Shared Costs and Expenses.  During the term of this
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Agreement, upon the reasonable request of PT3, PTI will make available to PT3
any of PTI's office and administrative personnel and facilities, consultants and
contractors, and general and administrative office overhead and costs, including
inter alia office space, record retention, photocopy facilities, facsimile and
telephone equipment, sales and marketing support, office supplies, and computer
services (collectively, the "Shared Costs and Expenses").

     2.   Reimbursement.  PT3 agrees to reimburse PTI for the costs and expenses
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incurred by PTI on behalf of or for the benefit of PT3 in an amount equal to the
sum of the following amounts (the "Reimbursement Amount") determined annually as
of the end of each calendar year:

            (a)   With respect to any Shared Costs and Expenses directly
     attributable solely to PT3, an amount equal to the marginal or incremental
     cost or expense thereof incurred by PTI; and

            (b)   With respect to any Shared Costs and Expenses not described in
     (a) above, the pro rata share of such Shared Costs and Expenses based on
     the product obtained by multiplying the gross amount of such Shared Costs
     and Expenses by the quotient obtained by dividing the gross revenues of PT3
     for the year by the sum of the gross revenues for the year of both PTI and
     PT3, or an amount determined on such other reasonable basis as the parties
     may mutually agree.

The Reimbursement Amount for each calendar year shall be determined no later
than three months after the end of such calendar year and payment of the
Reimbursement Amount shall be due on or before the April 10/th/ of the year
following the end of such calendar year.
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     3.   Standard of Care.  PTI agrees that it and its personnel shall exercise
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the same degree of diligence, care and prudence in connection with matters
conducted on behalf of, or provided for the benefit of, PT3 as it exercises
matters conducted on its own behalf or provided for its own benefit.

     4.   Limitation of Liability.
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             (a)   PTI and its Affiliates, and the officers, directors,
     employees, shareholders, partners, representatives, consultants and
     agents of PTI and its Affiliates (collectively, "Providing Parties")
     shall not be liable to the party on whose behalf the Shared Costs and
     Expenses are incurred, its Affiliates, or to any officer, director,
     employee, shareholder, partner, representative, consultant or agent of
     such party or its Affiliates (collectively, "Receiving Parties"), for
     any liability, cost, damage, expense or loss, including, without
     limitation, any special, indirect, consequential or punitive damages
     (i) arising or allegedly arising out of any actions or failures to act
     by any of the Providing Parties with respect to the Shared Costs and
     Expenses to be provided hereunder, or (ii) as a result of the reliance
     by any of the Receiving Parties on any advice or data that any of the
     Providing Parties may provide pursuant to this Agreement; provided,
     however, that the foregoing shall not apply to limit liability of a
     party to the extent caused by such party's gross negligence or willful
     misconduct.

             (b)   The Receiving Parties shall indemnify and hold harmless
     each and every of the Providing Parties from and against any
     liability, cost, damage, expense or loss (including court costs and
     reasonable attorneys' fees) which such Providing Parties may sustain
     or incur by reason of any claim, demand, suit or recovery by any
     person or entity, directly resulting from acts or omissions committed
     by the Receiving Party in connection with this Agreement; provided,
     however, that no person may benefit from the foregoing indemnity in
     the event of its gross negligence or willful misconduct.

     5.   Term.  The term of this Agreement shall commence as of the date hereof
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and end December 31, 2000, unless earlier terminated effective as of the end of
a calendar month by either party upon no less than two months' prior written
notice to the other party.  The term of this Agreement shall automatically renew
for successive periods of one year each unless either party provides to the
other party notice in writing that this Agreement will not so renew and such
notice is given at least two months prior to the then termination date of this
Agreement.  In the event this Agreement is terminated prior to the end of a
calendar year, the Reimbursement Amount shall be determined as of the effective
date of termination based on gross revenues of each party through the date of
termination.

     6.   Relationship of the Parties.  In all matters relating to this
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Agreement, each party hereto shall be solely responsible for the acts of its
employees, and employees of one party shall not be considered employees of the
other party.  No party shall have any right, power or authority to create any
obligation, express or implied, on behalf of any other party.  Nothing in this
Agreement is intended to create or constitute a joint venture or partnership
relationship between the parties hereto or persons referred to herein.

     7.   Force Majeure.  PTI shall be excused from performance hereunder for
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any period and to the extent that it is prevented from performance hereunder, in
whole or in part, as a result

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of delays caused by PT3 or any act of God, war, civil disturbance, court
order, strike, labor dispute, law or regulation of any governmental
authority, or other cause beyond the reasonable control of PTI. Such
nonperformance shall not be a default hereunder. PTI shall take all
reasonable actions to resume performance of its obligations hereunder as
soon as feasible.

     8.   Amendments and Waiver.  No amendment, waiver or consent with respect
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to any provision of this Agreement shall in any event be effective, unless the
same shall be in writing and signed by the parties hereto, and then such
amendment, waiver or consent shall be effective only in the specific instance
and for the specific purpose for which given.

     9.   Notices. All notices, requests, demands and other communications
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hereunder shall be in writing and shall be, personally delivered or sent by
facsimile transmission with confirming copy sent by overnight courier (such as
Express Mail, Federal Express, etc.) and a delivery receipt obtained and
addressed to the intended recipient as follows:

          If to PTI:

               Pinnacle Towers Inc.
               1549 Ringling Boulevard
               Third Floor
               Sarasota, Florida  34236
               Attention:  Ben Gaboury
               Telephone No.:  (941) 364-8886
               Facsimile No.:  (941) 364-8761

          If to PT3:

               Pinnacle Towers III Inc.
               1549 Ringling Boulevard
               Third Floor
               Sarasota, Florida  34236
               Attention:  Steve Day
               Telephone No.:  (941) 364-8886
               Facsimile No.:  (941) 364-8761

Any party may change its address or add or change parties for receiving notice
by written notice given to the others named above.  Notices shall be deemed
given as of the date of receipt.

     10.  Counterparts.  This Agreement may be executed in counterparts, each
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of which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

     11.  Successors and Assigns; Beneficiaries.  This Agreement shall bind and
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inure to the benefit of the parties named herein and their respective successors
and assigns. No party may assign any rights, benefits, duties or obligations
under this Agreement without the prior written consent of the other party.
Except as specifically provided in Section 4, no third party shall be entitled
to enforce any provision hereof; and no third party is intended to benefit from
this Agreement.

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     12.  Entire Agreement.  This Agreement and the documents referred to
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herein contain the entire agreement and understanding among the parties with
respect to the transactions contemplated hereby and supersede all other
agreements, understandings and undertakings among the parties on the subject
matter hereof.

     13.  Partial Invalidity.  In the event that any provision of this
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Agreement shall be held invalid or unenforceable by any court or competent
jurisdiction, such holding shall not invalidate or render unenforceable any
other provision hereof.

     14.  Governing Law; Jurisdiction.  This Agreement shall be interpreted in
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accordance with the substantive laws of the State of Florida applicable to
contracts made and to be performed wholly within said State.  All disputes,
legal actions, suits and proceedings arising out of or relating to this
Agreement shall be brought in a federal district or state court located in
Tampa, Florida.  Each party hereby consents to the jurisdiction of the federal
district or state court in Tampa, Florida.  Each party hereby irrevocably waives
all claims of immunity from jurisdiction and any right to object on the basis
that any dispute, action, suit or proceeding brought in the federal district or
state court of Tampa, Florida has been brought in an improper or inconvenient
venue or forum.

     15.  Disputes.
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            (a)   PTI and PT3 mutually desire that friendly collaboration
     will develop between themselves. Accordingly, they shall try to
     resolve in a friendly manner all disagreements and misunderstandings
     connected with their respective rights and obligations under this
     Agreement, including any amendments hereof.

            (b)   (i) To the extent that any misunderstanding or dispute
     cannot be resolved agreeably in a friendly manner, the dispute will be
     mediated by a mutually acceptable mediator to be chosen by PTI and PT3
     within forty-five (45) days after written notice by one of the parties
     demanding mediation. Neither party may unreasonably withhold consent
     to the selection of a mediator, however, by mutual agreement PTI and
     PT3 may postpone mediation until each has completed specified but
     limited discovery with respect to a dispute. The parties may also
     agree to attempt some other form of alternative dispute resolution
     ("ADR") in lieu of mediation, including by way of example and without
     limitation, neutral fact-finding or a mini-trial.

                  (ii) Any dispute which the parties cannot resolve through
     negotiation, mediation or other form of ADR within six months of the
     date of the initial demand for it by one of the parties may then be
     submitted to the courts for resolution. The use of any ADR procedures
     will not be construed under the doctrine of laches, waiver or estoppel
     to affect adversely the rights of either party. Nothing in this
     Section 15 will prevent either party from resorting to judicial
     proceedings if (A) good faith efforts to resolve the dispute under
     these procedures have been unsuccessful or (B) interim relief from a
     court is necessary to prevent serious and irreparable injury to one
     party or to others.

            (c)   Each of PT3 and PTI shall bear its costs of mediation or
     ADR, but PT3 and PTI agree to share the costs of the mediation of ADR
     equally.

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     16.  Authorship.  The parties hereto agree that the terms and language of
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this Agreement were the result of negotiations between the parties and, as a
result, there shall be no presumption that any ambiguities in this Agreement
shall be resolved against either party.  Any controversy over construction of
this Agreement shall be decided without regard to events of authorship or
negotiation.

     17.  Defined Terms.  All capitalized terms not defined herein shall have
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the meanings ascribed to them in the Asset Purchase Agreement.

     18.  Recitals. The recitals hereto are true and correct and are by this
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reference incorporated herein.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first above written.

                                   PINNACLE TOWERS INC.


                                   __________________________________
                                   Bernard Gaboury, President


                                   PINNACLE TOWERS III INC.



                                   __________________________________
                                   Steven R. Day, Vice President, Chief
                                   Financial Officer and Secretary

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