If a broker advertises or offers a guaranteed sale program, or other program whereby the broker undertakes to purchase real property in the event he or she is unable to effectuate a sale to a third party within a specified period of time, a written disclosure that sets forth clearly and completely the general terms and conditions under which the broker agrees to purchase the property and the disposition of any profit at the time of resale by the broker must be provided to the seller prior to the execution of a listing agreement.