(1) Where the broker has both parties to the purchase agreement for a flat or a single family house promise to pay a brokerage fee to the broker, this may be effected only such that both parties enter into obligation to pay the same amount. Where the broker agrees with one party to the purchase agreement that they will pursue their activities for that party at no charge, the broker may not have the other party promise them a brokerage fee. Any waiver of the fee takes effect also to the benefit of the respective other party contracting with the broker. It is not possible to deviate from sentence 3 by way of a contract.
(2) A brokerage contract in derogation from subsection (1) sentences 1 and 2 is ineffective. Section 654 remains unaffected.