Section 7. Any agreement to pay compensation for service as a broker or finder or for service rendered in negotiating a loan or in negotiating the purchase, sale or exchange of a business, its good will, inventory, fixtures, or an interest therein, including a majority of voting interest in a corporation, shall be void and unenforceable unless such agreement is in writing, signed by the party to be charged therewith, or by some other person authorized. For the purpose of this section, the term ''negotiating'' shall include identifying prospective parties, providing information concerning prospective parties, procuring an introduction to a party to the transaction or assisting in the negotiation or consummation of the transaction. The provisions of this section shall apply to a contract implied in fact or in law to pay reasonable compensation but shall not apply to a contract to pay compensation for professional services of an attorney-at-law or a licensed real estate broker or real estate salesman acting in their professional capacity.