Abstract: Disclosed is a system and method for assuring the payment according to a repayment schedule of an obligation for using equipment by a device on the equipment. A subset of a plurality reference codes is selected. The current time and date and time are maintained. Reference codes in the subset are assigned to a specific time interval, wherein the specific time interval is a portion of a time period corresponding to repayment schedule of the obligation for using the equipment. The subset of the plurality of codes, the specific individual time interval to which each code is assigned, and the time period is stored. A user code is received via an interface. The received user code is compared to the subset of reference codes, the current time, current date, and time period corresponding to repayment schedule of the obligation. Based on the results of the comparison the equipment is disabled.