645.77 External audit of receiver's books. The court in which the proceeding is pending may, as it deems desirable, cause audits to be made of the books of the commissioner relating to any receivership established under this chapter, and a report of each audit shall be filed with the commissioner and with the court. The books, records and other documents of the receivership shall be made available to the auditor at any time without notice. The expense of each audit shall be considered a cost of administration of the receivership.