Each operator shall, on or before the last day of the month following the close of each calendar quarter, or at the close of any shorter reporting period which may be established by the tax collector, make a return to the tax collector, on forms provided by him, of the total rents charged and received and the amount of tax collected for transient occupancies. At the time the return is filed, the full amount of the tax collected shall be remitted to the tax collector. The tax collector may establish shorter reporting periods for any certificate holder if he deems it necessary in order to insure collection of the tax and he may require further information in the return. Returns and payments are due immediately upon cessation of business for any reason. All taxes collected by operators pursuant to this chapter shall be held in trust for the account of the city until payment thereof is made to the tax collector. (Prior code § 1805)