Outstanding deposits received from customers and held by the city will be applied to customer's final bill upon termination and the difference, if any, will be refunded. In order to protect against customer's failure to pay, the city manager may require that a customer establish a deposit, an amount equal to the customer's average utility bills for a period of two months, if the customer has reflected an unsatisfactory payment history. The deposit will hold the city free from loss occasioned by the customer's failure to pay any utility bills rendered against him or her. (Prior code § 17-117)