The city collector, with the approval of the city controller, may make administrative agreements to vary the strict requirements of this chapter so that collection of any tax imposed herein may be made in conformance with the billing procedures of a particular service supplier so long as the overall result of said agreements results in collection of the tax in conformance with the general purpose and scope of this chapter. A copy of each such agreement shall be on file and available for public examination in the office of the city collector. (Prior code § 41.06.058)