Document:

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                                                                    Exhibit 10.8

                            PLACEMENT UNIT AGREEMENT

                  PLACEMENT UNIT AGREEMENT (this "Agreement") made as of this
24th day of August, 2006 by and among Harbor Business Acquisition Corp., a
Delaware corporation (the "Company"), H.C. Wainwright & Co., Inc. ("H.C.
Wainwright") and the undersigned (the "Purchasers").

                  WHEREAS, the Company intends to file with the Securities and
Exchange Commission ("SEC") a registration statement on Form S-1, (as may be
amended from time to time, the "Registration Statement"), in connection with the
Company's initial public offering (the "IPO") of up to 4,166,667 units
(including up to 625,000 units issuable upon exercise of an overallotment
purchase option granted to H.C. Wainwright, as representative of the
underwriters, by the Company), each unit ("Unit") consisting of (i) one share of
the Company's common stock, $0.001 par value (the "Common Stock"), and (ii) two
warrants (each such warrant, a "Warrant"), each Warrant to purchase one share of
Common Stock;

                  WHEREAS, the Company desires to sell in a private placement to
the Purchasers (the "Placement") an aggregate of 150,000 units (the "Placement
Units") substantially identical to the Units being issued in the IPO pursuant to
the terms and conditions hereof and as set forth in the draft Registration
Statement, previously distributed to the Purchasers except that the Placement
Units, Common Stock and Warrants to be issued in the Placement shall not be
registered under the Securities Act of 1933, as amended (the "Securities Act");

                  WHEREAS, each Purchaser desires to acquire the number of
Placement Units set forth opposite his name on Schedule A hereto;

                  WHEREAS, the Warrants included in the Placement Units shall be
governed by the Warrant Agreement to be filed as an exhibit to the Registration
Statement; and

                  WHEREAS, the Purchasers are entitled to registration rights
with respect to the Common Stock and the Warrants comprising the Placement Units
and the Common Stock underlying such Warrants (collectively, the "Registrable
Securities") on the terms set forth in this Agreement.

                  NOW, THEREFORE, for and in consideration of the premises and
the mutual covenants hereinafter set forth, the parties hereto do hereby agree
as follows:

                  1. Purchase of Units. The Purchasers hereby agree to purchase
an aggregate of 150,000 Placement Units at a purchase price of $6.00 per
Placement Unit, or an aggregate of $900,000 (the "Purchase Price"). Such
purchases shall be in the names and amounts set forth on Schedule A hereto.

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                  2. Closing. The closing of the purchase and sale of the
Placement Units (the "Closing") will take place at such time and place as the
parties may agree (the "Closing Date"), but in no event later than the date on
which the SEC declares the Registration Statement effective (the "Effective
Date"). On the Effective Date, the Purchasers shall pay the Purchase Price by
wire transfer of funds to an account maintained by the Company. Immediately
prior to the closing of the IPO, the Company shall deposit the Purchase Price
into the trust fund described in the Registration Statement (the "Trust
Account"). The certificates for the Common Stock and Warrants comprising the
Placement Units shall be delivered to the Purchasers promptly after the closing
of the IPO.

                  3. Voting of Shares. If the Company solicits approval of its
stockholders of a Business Combination, the Purchasers shall vote all of the
shares of the Common Stock acquired by the Purchasers (i) pursuant to this
Agreement, (ii) in the IPO and (iii) in the aftermarket following the IPO in
favor of the Business Combination and therefore waive any redemption or
conversion rights they might have with respect to certain of such shares. As
used herein, a "Business Combination" shall be as defined in the form of Amended
and Restated Certificate of Incorporation to be filed as an exhibit to the
Registration Statement.

                  4. Waiver of Liquidation Distributions. In connection with the
Placement Units purchased pursuant to this Agreement, the Purchasers hereby
waive any and all right, title, interest or claim of any kind in or to any
liquidating distributions by the Company in the event of a liquidation of the
Company upon the Company's failure to timely complete a Business Combination.
For purposes of clarity, any shares of Common Stock purchased in the IPO or the
aftermarket by the Purchasers shall be eligible to receive any liquidating
distributions by the Company.

                  5. Rescission Right Waiver and Indemnification.

                  5.1 Each of the Purchasers understands and acknowledges that
an exemption from the registration requirements of the Securities Act requires
that there be no general solicitation of purchasers of the Placement Units. In
this regard, if the offering of the Units in the Company's IPO were deemed to be
a general solicitation with respect to the Placement Units, the offer and sale
of such Placement Units may not be exempt from registration and, if not, the
Purchasers may have a right to rescind their purchases of the Placement Units.
In order to facilitate the completion of the Placement and in order to protect
the Company, its stockholders and the Trust Account from claims that may
adversely affect the Company or the interests of its stockholders, each of the
Purchasers hereby agrees to waive, to the maximum extent permitted by applicable
law, any claims, right to sue or rights in law or arbitration, as the case may
be, to seek rescission of its purchase of the Placement Units. Each of the
Purchasers acknowledges and agrees that this waiver is being made in order to
induce the Company to sell the Placement Units to the Purchasers. Each Purchaser
agrees that the foregoing waiver of rescission rights shall apply to any and all
known or unknown actions, causes of action, suits, claims, or proceedings
(collectively, "Claims") and related losses, costs, penalties, fees, liabilities
and damages, whether compensatory, consequential or exemplary, and expenses in
connection therewith, including reasonable attorneys' and expert witness fees
and disbursements and all other expenses reasonably incurred in investigating,
preparing or defending against any Claims, whether pending or threatened, in
connection with any present or future actual or asserted right to rescind the
purchase of the Placement Units hereunder or relating to the purchase of the
Placement Units and the transactions contemplated hereby (collectively, "Losses
and Expenses").
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                  5.2 Each Purchaser agrees not to seek recourse against the
Trust Account for any reason whatsoever in connection with his purchase of the
Placement Units or any Claim that may arise now or in the future.

                  5.3 The Purchasers acknowledge and agree that the stockholders
of the Company are and shall be third-party beneficiaries of the foregoing
provisions of this Agreement.

                  5.4 Each Purchaser agrees that to the extent any waiver of
rights under this Section 5 is ineffective as a matter of law, each Purchaser
has offered such waiver for the benefit of the Company as an equitable right
that shall survive any statutory disqualification or bar that applies to a legal
right. Each Purchaser acknowledges the receipt and sufficiency of consideration
received from the Company hereunder in this regard.

                  6. Lock-Up Agreement; Deposit with H.C. Wainwright. The
Purchaser shall not offer, sell, contract to sell, pledge, hypothecate or
otherwise dispose of, directly or indirectly, the Placement Units or any of the
Common Stock or Warrants underlying the Placement Units purchased pursuant to
this Agreement, enter into a transaction that would have the same effect, or
enter into any swap, hedge or other arrangement that transfers, in whole or in
part, any of the economic consequences of ownership of such securities, whether
any such aforementioned transaction is to be settled by delivery of such
securities or such other securities, in cash or otherwise, or publicly disclose
the intention to make any such offer, sale, pledge or disposition, or to enter
into any such transaction, swap, hedge or other arrangement until the
consummation of a Business Combination. In order to enforce this covenant, if
requested by H.C. Wainwright, the undersigned agree to deposit the Placement
Units in an account to be established at H.C. Wainwright to be held in such
account until the consummation of a Business Combination.

                  7. Representations and Warranties of the Purchasers. Each
Purchaser hereby represents and warrants to the Company that:

                  7.1 The Purchaser is an "accredited investor" as that term is
defined in Rule 501 of Regulation D promulgated under the Securities Act.

                  7.2 The Purchaser understands that the Placement Units, the
Warrants and the Common Stock are characterized as "restricted securities" under
the U.S. federal securities laws inasmuch as they are being acquired from the
Company in a transaction not involving a public offering and that under such
laws and applicable regulations such securities may be resold without
registration under the 1933 Act only in certain limited circumstances.

                  7.3 The Placement Units, Common Stock and Warrants are being
acquired for the Purchaser's own account, only for investment purposes and not
with a view to, or for resale in connection with, any distribution or public
offering thereof within the meaning of the Securities Act.
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                  7.4 The Purchaser acknowledges that it can bear the economic
risk and complete loss of its investment in the Placement Units, Common Stock
and Warrants and has such knowledge and experience in financial or business
matters that it is capable of evaluating the merits and risks of the investment
contemplated hereby.

                  7.5 The Purchaser has the full right, power and authority to
enter into this Agreement and this Agreement is a valid and legally binding
obligation of the Purchaser enforceable against the Purchaser in accordance with
its terms.

                  8. Registration Rights. The Purchaser will be entitled to the
benefit of the registration rights granted pursuant to the Registration Rights
Agreement among the Company and the parties named therein and the Placement
Units, Common Stock and Warrants shall be deemed "Registrable Securities" under
such Registration Rights Agreement.

                  9. Waiver of Claims; Indemnification. Each Purchaser hereby
waives any and all rights to assert any present or future claims, including any
right of rescission, against the Company, H.C. Wainwright or the other
underwriters in the IPO exclusively with respect to their purchase of the
Placement Units hereunder, and each Purchaser agrees to indemnify and hold the
Company, H.C. Wainwright and the other underwriters in the IPO harmless from all
losses, damages or expenses that relate to claims or proceedings brought against
the Company, H.C. Wainwright or such other underwriters by such Purchaser of the
Placement Units arising solely out of the purchase of the Placement Units
hereunder.

                  10. Counterparts; Facsimile. This Agreement may be executed in
any number of counterparts, each of which when so executed shall be deemed to be
an original and all of which taken together shall constitute one and the same
instrument. This Agreement or any counterpart may be executed via facsimile
transmission, and any such executed facsimile copy shall be treated as an
original.

                  11. Governing Law. This Agreement shall for all purposes be
deemed to be made under and shall be construed in accordance with the laws of
the State of New York. Each of the parties hereby agrees that any action,
proceeding or claim against it arising out of or relating in any way to this
Agreement shall be brought and enforced in the courts of the State of New York
or the United States District Court for the Southern District of New York, and
irrevocably submits to such jurisdiction, which jurisdiction shall be exclusive.
Each of the parties hereby waives any objection to such exclusive jurisdiction
and that such courts represent an inconvenient forum.

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IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the 24th
day of August, 2006.

                                     HARBOR BUSINESS ACQUISITION CORP.

                                     By:    /s/ W. Thomas Lomax
                                         --------------------------------------
                                         Name:  W. Thomas Lomax
                                         Title: Chairman of the Board

                                     H.C. WAINWRIGHT & CO., INC.

                                     By:    /s/ Anthony J. Sarkis
                                         --------------------------------------
                                         Name:  Anthony J. Sarkis
                                         Title: Director of Investment Banking

                                     PURCHASERS:

                                     HARBOR HEALTHCARE HOLDING LLC

                                     By:    /s/ W. Thomas Lomax
                                         --------------------------------------
                                         Name:  W. Thomas Lomax
                                         Title: President

                                     MORECO PARTNERS LLC

                                     By:    /s/ Robert Moreyra
                                         --------------------------------------
                                         Name:  Robert Moreyra
                                         Title: Managing Member

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SCHEDULE A

PURCHASER                               AMOUNT
---------                               ------
Harbor Healthcare Holding LLC           130,000 Units
Moreco Partners LLC                     20,000 Units
TOTAL                                   150,000 UnitsAMENDMENT

This Amendment applies to the Revolving Credit Agreement ("Agreement") dated
November 1, 2004 between Avante Holding Group, Inc. ("Avante") and Alternative
Construction Company, Inc. ("ACC").

The Agreement provides a Line of Credit ("LOC") of $500,000. This Amendment
provides an additional $500,000 to the LOC thereby providing a total of
$1,000,000 for the LOC.

The terms of this Amendment are the same as the Agreement.

ALTERNATIVE CONSTRUCTION COMPANY, INC.

/s/ Thomas G. _____
----------------------------------------
Name: Thomas G. _____
Title: Secretary

AVANTE HOLDING GROUP, INC.

/s/ Michael W. Hawkins
-----------------------------------------
Name: Michael W. Hawkins
Title: President

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