A certified public accountant or firm may not accept or pay a commission or referral fee in connection with the sale or referral of public accounting services as defined in s. 473.302(8)(a) and (c). Any certified public accountant or firm that is engaged in the practice of public accounting and that accepts a commission for the sale of a product or service to a client must disclose that fact to the client in writing in accordance with rules adopted by the board. However, this section shall not prohibit:
(1) Payments for the purchase of an accounting practice;
(2) Retirement payments to individuals formerly engaged in the practice of public accounting or payments to their heirs or estates; or
(3) Payment of fees to a referring certified public accountant or firm for public accounting services to the successor certified public accountant or firm or the client in connection with an engagement.