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                                                                   Exhibit 10.66


                BROKER-DEALER PLACEMENT AGENT SELLING AGREEMENT

         This agreement is made as of May ___, 2003 by and between Invisa, Inc.,
a corporation organized under the laws of the State of Nevada, with its
principal place of business at 4400 Independence Court, Sarasota, Florida 34234
("Company") and Capstone Partners, L.C., a limited liability company organized
under the State of Utah, with its principal place of business at 3475 Lenox
Road, Suite 400, Atlanta, GA 30326.

The Company hereby agrees with Broker as follows:

1.       Broker is a registered broker-dealer and a member of the National
         Association of Securities Dealers, Inc. ("NASD"), a part of whose
         business consists of the sale or placement of securities. Broker is
         also registered as a broker-dealer under the securities laws of one or
         more states of the United States, including the State of Florida.

2.       The Company intends to offer and sell to qualified investors, shares of
         common stock or other of its securities ("Securities") upon the terms
         and conditions set forth in negotiated financing transactions hereafter
         to be developed and agreed upon by the Company with the assistance of
         the Broker. At present, it is the intention of the parties that a
         maximum of $1,000,000 aggregate offering amount will be raised through
         the placement of an Equity Line of Credit for the Company, which is
         intended to qualify as a private placement of Securities pursuant to
         exemptions from registration afforded by the Securities Act of 1933 and
         applicable state law exemptions consistent therewith. This Agreement
         covers placement agent services and compensation solely with regard to,
         and is limited to, the placement and finalization of the Equity Line of
         Credit, including the Advance, as agreed by the Company in its term
         sheet with BARBELL GROUP , INC providing for same dated April 25, 2003
         (the "Equity Line of Credit").

3.       Broker desires to participate in the placement of the Securities for
         the Equity Line of Credit on a "best efforts" basis by soliciting,
         through Broker's authorized personnel, or through other broker-dealers
         selected as dealers acting as additional placement agents,
         subscriptions for the purchase of the Securities in accordance with the
         terms of the financing arrangements agreed upon with the Company. The
         Company desires to authorize Broker to obtain such subscriptions and to
         seek sources of financing consistent with the Company's interests and
         it is the purpose of this Agreement to set forth the agreement of the
         parties relative to such authorization.

4.       Broker understands and acknowledges that the offering and sale of the
         Securities to be offered by the Company have not been and will not be
         registered with the U.S. Securities & Exchange Commission or any other
         state regulatory agency, and the Securities will be offered and sold in
         reliance upon the exemptions from registration contained in Section
         4(2) of the Securities Act of 1933, as amended (the "Act") and
         Regulation D (Rule 506) promulgated thereunder, as well as various
         exemptions from registration or qualification afforded by the "blue
         sky" laws of those jurisdictions in which the Securities are offered or
         sold. Securities offered and sold in exchange for the Company's
         financing shall only be made to and subscriptions accepted from
         "accredited investors" as defined in Rule 501 of Regulation D
         promulgated under the Act.

5.       Broker shall solicit subscriptions to purchase the Securities in
         compliance with all applicable Federal and state securities laws and
         the provisions of this Agreement. Copies of any offering documents
         authorized for distribution by the Company will be furnished to the
         Broker in reasonable quantities upon specific request. All copies of
         the offering documents and any other printed or written materials
         furnished to Broker in connection with the offering shall remain the
         property of the Company, shall be treated and cared for as set out in
         this Agreement and shall be returned to the Company forthwith upon
         request. Broker shall maintain a written record reflecting the
         distribution and location of all materials furnished in connection with
         the offering and the identity of all persons to whom such materials are
         distributed. In addition, Broker shall use its best efforts to: (i)
         assure that the materials furnished are treated as confidential and not
         reproduced or redistributed; and (ii) secure the return of all
         materials furnished to persons who

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         do not subscribe for the Shares. Neither Broker nor any officer, agent
         employee or other representative of Broker is authorized to utilize or
         to display to any person, in connection with the solicitation of
         subscriptions for the Securities any information or material other than
         the offering documents and such other information or material as may be
         authorized and actually furnished by the Company to Broker in
         connection with the Offering.

6.       The offering of the Securities will terminate in accordance with the
         request of the Company, but may be continued by the Company within its
         discretion. The Company shall have the right, in its sole discretion,
         to accept or reject any subscriptions tendered by Broker in whole or in
         part. Subscriptions need not be accepted in the order in which they are
         received.

7.       If applicable to the transaction, all funds received by the Company
         from subscriptions tendered by Broker and accepted by the Company shall
         be deposited in an escrow account at a qualified "bank" in order to
         comply with Rule 15c2-4 under the Securities Exchange Act of 1934
         ("Escrow Account") until subscription agreements relative to each
         purchaser of Securities have been received and accepted by the Company.
         Upon receipt and acceptance of one or more subscription agreements by
         the Company, funds will be promptly released to the Company from the
         above mentioned depository account for such accepted subscription
         agreements for uses as set forth in any offering documents. In this
         fashion, the offering will continue up to and including the termination
         date or until the maximum aggregate amount of the offering is received
         by the Company, whichever event occurs first.

         Upon the acceptance of the Equity Line of Credit approved by the
         Company, Broker will be entitled to receive compensation and/or
         commissions as described below:

                  (i)      Thirteen (13%) percent as a commission based on the
                           principal amount of investment funds actually
                           received by the Company from the Equity Line of
                           Credit that were placed through the direct and
                           indirect placement efforts of the Broker; provided
                           however;

                           (ii)     Of the total commission due at the initial
                                    closing of the initial $250,000 in aggregate
                                    amount of investment proceeds received by
                                    the Company, $17,500 shall be paid in cash
                                    ("Advance Fee") and the balance of $15,000
                                    deferred for payment as set forth herein
                                    ("Deferred Fee"); of the total amount of the
                                    Advance Fee payable hereunder, two-thirds or
                                    66.7% of the Advance Fee shall be earned by
                                    the Broker and one-third or 33.3% of the
                                    Advance Fee shall be earned by and paid over
                                    to Crescent Fund, Inc. by the Broker as a
                                    finder's fee on behalf of Crescent Fund,
                                    Inc.

                           (iii)    The Deferred Fee shall be delivered to the
                                    Broker at the closing of the initial
                                    $250,000 in aggregate amount of investment
                                    proceeds received by the Company in the form
                                    of 6,000 shares of restricted common stock
                                    to issue by the Company ("Stock Fee"). Of
                                    the total amount of the Deferred Fee payable
                                    hereunder, two-thirds or 66.7% of the
                                    Advance Fee (4,000 shares of INSA common
                                    stock) shall be earned by the Broker and
                                    one-third or 33.3% of the Deferred Fee
                                    (2,000 shares of INSA common stock) shall be
                                    earned by and paid over to Crescent Fund,
                                    Inc. by the Broker as a finder's fee on
                                    behalf of Crescent Fund, Inc. By virtue of
                                    this Agreement, the shares issued in payment
                                    of the Stock Fee shall be included in the
                                    registration statement to be required as
                                    part of the Equity Line of Credit. The
                                    Company shall have a right of redemption in
                                    favor of the Company covering the 6,000
                                    shares of common stock at a redemption price
                                    equal to $15,000; and

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                           (iv)     In the event that the shares issued in
                                    payment of the Stock Fee are not covered by
                                    an effective registration statement filed
                                    with the SEC or, in the alternative, are not
                                    redeemed by the Company within the earlier
                                    of: (i) 120 days of the date of May 12,
                                    2003; or (ii) the date that the Company pays
                                    the Note, as defined in the Investment
                                    Agreement covering the Equity Line of
                                    Credit, then the record holders of said
                                    shares shall have the right to "put" the
                                    6,000 shares to the Company at $15,000 plus
                                    10% per annum interest.

                           (v)      Compensation to be paid to the Broker on all
                                    investment amounts received by the Company
                                    under the Equity Line of Credit, except the
                                    conversion of the initial $250,000 Advance,
                                    shall be paid to Broker out of the proceeds
                                    of all Put Amounts as defined in the Equity
                                    Line of Credit Investment Agreement, and
                                    shall equal 13% in cash on the Put Amounts
                                    received. Of the total amount of the
                                    compensation payable under the Equity Line
                                    of Credit, two-thirds or 66.7% of the fees
                                    shall be earned by the Broker and one-third
                                    or 33.3% of the fees shall be earned by and
                                    paid over to Crescent Fund, Inc. by the
                                    Broker as a finder's fee on behalf of
                                    Crescent Fund, Inc.

         The Company shall have no liability or obligation to Broker for any
         amount other than the cash commissions and Stock Fee provided for
         herein. The cash commissions and Stock Fee shall be deliverable only
         if, as, and when investor's funds are received by the Company pursuant
         to this section and pursuant to the financing to be placed by the
         Broker.

8.       The Company represents and warrants to Broker and agrees as follows:

         (a)      The Company is a "C" corporation duly organized and validly
                  existing under the laws of the State of Nevada with all the
                  requisite power and authority to enter into and perform this
                  Agreement.

         (b)      The Company is not in violation of its Articles of
                  Incorporation; the Company is not in default in the
                  performance or observance of any material obligation
                  agreement, covenant or condition contained in any material
                  contract, indenture mortgage, loan agreement, note, lease, tax
                  return or other agreement or instrument to which it is a party
                  or by which it or any of its properties is bound; and the
                  execution and delivery of this Agreement, the consummation of
                  the transactions contemplated herein and compliance with the
                  terms hereof have been duly authorized by all necessary action
                  and do not and will not result in any violation of the
                  Articles of Incorporation of the Company and do not and will
                  not conflict with, or result in a breach of any of the tenets
                  or provisions of, or constitute a default under, or result in
                  the creation or imposition of any lien, charge or encumbrance
                  upon any property or assets of the Company under, any material
                  indenture, mortgage loan agreement, note, lease, or other
                  agreement or instrument to which the Company is a party or by
                  which it or any of its properties is bound, or any existing
                  applicable law, rule, regulation, judgment, order or decree of
                  any government, governmental instrumentality or court,
                  domestic or foreign, having jurisdiction over the Company or
                  any of its properties.

         (c)      This Agreement has been duly executed and delivered by the
                  Company and constitutes a legal, valid and binding obligation,
                  enforceable in accordance with its terms.

         (d)      Except as may be provided in the Equity Line of Credit, the
                  offer and sale of the Securities has not been and will not be
                  registered with the Securities and Exchange Commission or any
                  other regulatory agency; and insofar as such matters may be
                  subject to the control of the Company, the Securities will be
                  offered in compliance with the requirements of Sections 4(2)
                  and/or 4(6) of the Act and Regulation D promulgated

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                  there under, various exemptions from registration or
                  qualification afforded by the "blue sky" laws of those
                  jurisdictions in which the Securities are offered or sold and
                  all other applicable laws, with a view to ensuring that the
                  offering and sale of the Securities will be exempt from the
                  registration or qualification requirements of the Federal and
                  applicable state securities laws as a transaction not
                  involving any public offering. The Company warrants that all
                  appropriate state notices and related filings have been or
                  will be timely filed in accord with all appropriate "blue sky"
                  requirements of each state or other jurisdiction wherein the
                  offering and sale of the Securities shall occur.

         (e)      All offering documents and all amendments thereto, and all
                  collateral sales materials, will not, as of its date, include
                  any untrue statement of a material fact or omit to state any
                  material fact required to be stated or necessary to make the
                  statements made therein not misleading.

         (f)      The Company shall provide to Broker and to each offeree and
                  his purchaser representative any such information, documents
                  and instruments as may be reasonably requested pursuant to
                  Regulation D and to otherwise comply with such requirements of
                  that rule.

         (g)      The Company agrees not to accept subscriptions for the
                  Securities from persons that do not qualify as "accredited
                  investors" within the definition contained in Rule 501 of
                  Regulation D promulgated under the Securities Act of 1933.

         (h)      The Company, as well as its affiliates, acknowledges that the
                  chief executive officer and controlling shareholder of the
                  Broker, is an attorney licensed to practice law in one or more
                  states and has rendered legal services to the Company, as well
                  as the Company's corporate predecessor(s) in the areas of
                  Federal and state securities law and regulation prior to the
                  date of this Agreement. Accordingly, the Company acknowledges
                  that this Agreement does not provide for the delivery of legal
                  services by the Broker or its chief executive officer, nor are
                  any such legal services contemplated or to be delivered to the
                  Company by separate agreement. Further, that the Company
                  represents and warrants that it intends to rely upon and
                  obtain separate legal representation and advice concerning any
                  and all aspects of the Offering and the Offering Documents.

9.       Broker represents and warrants to the Company and agrees as follows:

         (a)      Broker is a limited liability company duly organized and
                  validly existing under the laws of the State of Utah with
                  corporate power and authority to enter into and perform all of
                  its obligations under this Agreement.

         (b)      Broker, if a corporation or limited liability company, is not
                  in violation of its Certificate of Incorporation, Agreement,
                  or By-laws; Broker is not in default in the performance or
                  observance of any material obligation, agreement, covenant or
                  condition contained in any material contract, indenture,
                  mortgage, loan agreement, note, lease, tax return or other
                  agreement or instrument to which it is a party or by which it
                  or any of its properties is bound; and the execution and
                  delivery of this Agreement, the consummation of the
                  transactions contemplated herein and compliance with the terms
                  hereof have been duly authorized by all necessary action and
                  do not and will not result in any violation of the Certificate
                  of Incorporation, Agreement, or By-laws of Broker, if any, and
                  do not and will not conflict with, or result in a breach of
                  any of the tenets or provisions of, or constitute a default
                  under, or result in the creation or imposition of any lien,
                  charge or encumbrance upon any property or assets of Broker
                  under, any material indenture, mortgage, loan agreement, note,
                  lease or other agreement or instrument to which Broker is a
                  party or by which it or any of its properties is bound, or any
                  existing applicable law, rule, regulation, judgment, order or
                  decree of any government,

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                  governmental instrumentality or court, domestic or foreign,
                  having jurisdiction over Broker or any of its properties.

         (c)      This Agreement has been duly executed and delivered by Broker
                  and constitutes the legal, valid and binding obligations of
                  Broker, enforceable against it in accordance with its terms.

         (d)      Broker is duly registered pursuant to the provisions of the
                  Securities Exchange Act of 1934 as a dealer and it is duly
                  registered as a broker-dealer in such states that it is
                  required to be so registered in order to carry out the
                  offering contemplated by this Agreement.

         (e)      Broker will: (i) conduct the offering and sale of the
                  Securities in accordance with the provisions of Federal and
                  applicable state securities laws and preserve for the Company
                  the exemption from registration or qualification provided by
                  Sections 4 (2) and/or 4(6) of the Act and/or Regulation D
                  promulgated under the Act and under comparable state
                  securities laws; and (ii) limit the offering of the Securities
                  to persons who meet the suitability standards set forth in the
                  Offering Documents and, prior to any offer of the Securities
                  to any such persons, have reasonable grounds to believe, and
                  in fact believe, that such person meets such standards and
                  maintain memoranda and other appropriate records
                  substantiating the foregoing.

         (f)      If Broker or agents or salesmen of Broker act as a purchaser
                  representative with respect to the Securities, such person
                  shall comply with the requirements of appointment, notice and
                  disclosure contained in Regulation D.

         (g)      Broker will limit the offering of the Securities to
                  solicitations of subscriptions in accordance with Sections
                  4(2) and/or 4(6) of the Act or Rule 506 of Regulation D
                  promulgated under the Act, and will provide each offeree with
                  a complete copy of the Offering Documents (including all
                  supplements, amendments and exhibits thereto) during the
                  course of the Offering and prior to sale.

         (h)      Broker will, prior to sale afford each offeree and his
                  purchaser representative, if any, the opportunity to ask
                  questions of and receive answers from the Company concerning
                  the terms and conditions of the offering and to obtain any
                  additional information, to the extent possessed by the Company
                  or obtainable by it without unreasonable effort or expense,
                  necessary to verify the accuracy of the information contained
                  in the Offering Documents.

         (i)      Broker will not use or employ any information or materials in
                  connection with the offering and sale of the Securities other
                  than the offering documents, unless the same shall have been
                  provided by the Company, and then only if the same are
                  accompanied or preceded by the offering documents.

         (j)      Broker will obtain and forward to the Company all
                  documentation required to accompany subscriptions for
                  Securities, fully and properly completed.

10.      Indemnification:

         (a)      The Company shall indemnify, and hold harmless, Broker and
                  each person, if any, who controls Broker, as well as any and
                  all employees, agents, representatives and joint venture
                  affilates of the Broker (within the meaning of either the Act
                  or the Securities Exchange Act of 1934), as follows:

                  (i)      Against any and all loss, claim, damage, liability
                           and expense, whatsoever arising out of any untrue
                           statement of a material fact contained in the
                           Offering

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                           Documents (or any amendment or supplement thereto),
                           or the omission or alleged omission there from of a
                           material fact required to be stated therein or
                           necessary to make the statements therein not
                           misleading;

                  (ii)     Against any and all loss, liability, claim, damage
                           and expense whatsoever to the extent of the aggregate
                           amount paid in settlement of any litigation, or
                           investigation or proceeding by any governmental
                           agency or body, commenced or threatened, or any such
                           alleged untrue statement or omission, if such
                           settlement is effected with the written consent of
                           the Company; and against any and all expense
                           whatsoever (including fees and disbursements of
                           counsel chosen by Broker and approved by the Company,
                           which approval shall not be unreasonably withheld)
                           reasonably incurred in investigating, preparing or
                           defending against any litigation or investigation or
                           proceeding by any governmental agency or body,
                           commenced or threatened, or any claim whatsoever
                           based upon any such untrue statement or omission, or
                           any such alleged untrue statement or omission or
                           based upon any "blue sky" filings, or lack thereof.
                           It shall be the Company's responsibility to only
                           accept subscription in states where the Company's
                           securities attorney has properly filed Form D with
                           the state of residence of the subscriber or in States
                           where the offer and sale of the Securities would be
                           otherwise permissible pursuant to the securities laws
                           and regulations governing offers and sales of such
                           securities in such states; and

                  (iii)    Against any claim or obligation made by Crescent
                           Fund, Inc., a Texas corporation ("Crescent"), whose
                           address is 67 Wall Street, New York, NY 10005 against
                           the Company for compensation that Crescent may claim
                           under that certain Consulting Agreement entered into
                           between Crescent and the Company dated March 6, 2003
                           as a result of the Broker's success in locating one
                           or more sources of investment capital for the
                           Company.

         (b)      Broker shall indemnify and hold harmless the Company, each
                  director and officer of the Company, and each person who
                  controls the Company (within the meaning of either the Act or
                  the Securities Exchange Act of 1934), each consultant or
                  financial advisor of the Company, and each agent, attorney, or
                  representative of the Company, in the same manner and to the
                  extent set forth in subsection 11(a), against any and all
                  loss, claim, damage, liability and expense described in
                  subsection 11(a), but only with respect to false or misleading
                  statements, or alleged false or misleading statements, made by
                  Broker, or any officer, director, employee or agent of Broker,
                  not contained in the offering documents.

         (c)      Each indemnified party shall give prompt notice to each
                  indemnifying party of any action commenced against it in
                  respect of which indemnity may be sought hereunder, but
                  failure to so notify any indemnifying party shall not relieve
                  it from any liability which it may have otherwise than on
                  account of this indemnity agreement. An indemnifying party may
                  participate at its own expense in the defense of such action.
                  In no event shall the indemnifying parties be liable for the
                  fees and expenses of more than one counsel for all indemnified
                  parties in connection with any one action or separate but
                  similar or related actions in the same jurisdiction arising
                  out of the same general allegations or circumstances.

         (d)      If the indemnification provided for in Section 10(a) or 10(b)
                  hereof is unenforceable although applicable in accordance with
                  its terms, then the parties agree that in order to provide for
                  just and equitable contribution, they each shall
                  proportionately contribute to the aggregate losses, claims,
                  damages, liabilities or expenses contemplated by such
                  indemnity agreement incurred by each of them, provided,
                  however, that no person guilty of fraudulent misrepresentation
                  (within the meaning of Section 9(f) of the Act)

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                  shall be entitled to contribution from any person who was not
                  guilty of such fraudulent misrepresentation. For purposes of
                  this Section 11, each person, if any, who controls the Company
                  or Broker within the meaning of either the Act or the
                  Securities Exchange Act of 1934 shall have the same rights to
                  contribution as the Company and Broker.

12.      All representations, warranties, covenants and agreements made herein
         or in certificates and instruments delivered pursuant hereto, as well
         as the indemnification provisions contained in Section 11 hereof, shall
         remain in full force and effect regardless of any investigation made by
         or on behalf of Broker and its controlling persons, or the Company and
         its controlling persons, or any agent of any of them, and shall survive
         sale and delivery of the Securities to be offered under any offering
         documents and this Agreement.

13.      All notices hereunder shall be in writing, and shall be personally
         delivered or sent by first class registered or certified mail, postage
         prepaid, to the parties at their respective addresses shown below, or
         such other addresses as may be so designated.

14.      Time shall be of the essence of this Agreement.

15.      This Agreement (other than those portions that survive) may be
         terminated by either party at any time by written notice to the other
         party.

16.      Any controversy or claim arising out of or relating to this Agreement,
         or the breach thereof, or its interpretation or effectiveness, and
         which is not settled between the parties themselves, shall be settled
         by binding arbitration in Fulton County, Georgia in accordance with the
         rules of the American Arbitration Association and judgment upon the
         award may be entered in any court having jurisdiction thereof. The
         prevailing party in any litigation, arbitration or mediation relating
         to collection of fees, or any other matter under this Agreement, shall
         be entitled to recover all its costs, if any, including without
         limitation reasonable attorney's fees, from the other party for all
         matters, including, but not limited to, appeals. This Agreement is made
         in the State of Georgia, and all questions related to the execution,
         construction, validity, interpretation and performance of this
         Agreement and to all other issues or claims arising hereunder, should
         be governed and controlled by the laws of the State of Georgia.

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

Company:                                   Broker Dealer
Invisa, Inc.                               Capstone Partners, L.C.
A Nevada corporation                       A Utah limited liability company


By: Stephen A. Michael, President          By: Gregory Bartko
    -----------------------------              ---------------------------------
    Steve Michael, President                   Gregory Bartko, CEO

Agreed To And Accepted By:
Crescent Fund, Inc, (as to Section 7 Only). By execution hereof, Crescent Fund,
Inc agrees that the compensation to be paid by Invisa, Inc. to Capstone
Partners, LC as provided herein fully and completely satisfies Invisa, Inc.'s
obligation to Crescent Fund, Inc, under the Agreement between Crescent Fund, Inc
and Invisa, Inc. dated March 6,2003, with regard to any compensation due to
Crescent Fund, Inc, arising out of or relating to the Equity Line of Credit
defined herein and funding from Barbell group, Inc.

By: Jeffery Stone
    -----------------------------
    Jeff Stone, Its _____________


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