Mo. Rev. Stat. § 180.130

The librarian may collect a reasonable fee for reproducing legal material. The librarian may make expenditures from these fees in order to secure legal material from other sources. A single expenditure from these fees shall not exceed twenty dollars. The aggregate of all expenditures from these fees during any fiscal year shall not exceed two hundred fifty dollars. Accurate records of all receipts and expenditures shall be maintained at all times. The balance of the fees shall be paid into the state treasury at least monthly.