The listing agreement usually specifies the amount of commission as a percentage of the sales price. The court will determine, in its discretion, what is a reasonable commission (Cal. Prob. Code §§ 10150((b), 10161(a)). However, the court may not approve an amount in excess of the maximum percentage established by local court rules. This amount can be determined by contacting the clerk of the probate court of the county in which the estate is being administered.

Local court rules do vary. For example: Los Angeles County Superior Court Rule 10.93 limits commission to 5% except in the case of vacant land; Orange County Superior Court Rule 606.06 limits commission to 6% unless justified by exceptional circumstances.
If a sale is confirmed by the court and subsequently closes, the listing broker has earned the commission specified in the listing contract, not to exceed the maximum percentage allowed by local court rules. The commission, also, may not exceed the amount provided for in the listing contract (Cal. Prob. Code § 10161(c)).

For Example :  If the maximum under local rules is five percent and the broker‘s listing contract specifies four percent, the broker is limited to a four percent commission. Conversely, if the commission in the listing contract is six percent and the maximum under local rules is five percent, the listing broker‘s fee is limited to five percent.