When a licensee prepares or has prepared an agreement authorizing the licensee to perform any of the acts for which the licensee is required to hold a license, or when such licensee secures the signature of any party or parties to any contract pertaining to such services or transaction, the licensee shall deliver a copy of the agreement or contract to the party or parties signing it, at the time the signature is obtained; provided that only one copy need be delivered to parties signing as cotenants.