Establishing that a presumed agency relationship between a real estate broker licensee and a buyer or lessee terminates if 3 months have passed since the licensee and the buyer or lessee entered into the relationship; establishing that the burden is on the licensee to establish that a presumed agency relationship has not terminated under specified provisions of law; requiring a brokerage agreement to contain a termination date no later than 90 days after the date on which the agreement was entered into; etc.