Owner, Broker and Agent Fee Split

An estate inherited a real estate brokerage business that managed around 85 properties. The structure was a single agent and an owner/broker with a fee split. The estate needs to get a broker to manage the duties of broker in the interim prior to the business being sold. What is a reasonable fee structure between owner, broker and agent. The business is in california. The previous broker/owner made 3-4k monthly in fees.