An intermediary is a broker who negotiates the transaction between the parties when the broker or a sales agent sponsored by the broker has obtained consent from the parties to represent both the buyer and the seller. The broker intermediary may, with the written consent of the parties, appoint separate individual license holder associated with the broker to work with and advise the party to whom they have been appointed. [TRELA §§ 1101.558-1101.561 and §1101.651(d)]