Section 74209 - Accounting Records(a) Accounting records shall contain billing records, including copies of invoices and copies of receipts for each and every financial transaction conducted in the course of the referral agency's business.(b) There shall be on file in the referral agency a copy of each service agreement or contract made by the agency and any health facility and those made by the agency with any client with whom the agency has agreed or contracted.Cal. Code Regs. Tit. 22, § 74209