CA Prob Code Section 8921

The court may designate a person requested by the personal representative as probate referee, on a showing by the personal representative of good cause for the designation. The following circumstances are included within the meaning of good cause, as used in this section:

(a)

The probate referee has recently appraised the same property that will be appraised in the administration proceeding.

(b)

The probate referee will be making related appraisals in another proceeding.

(c)

The probate referee has recently appraised similar property in another proceeding.