While the LeaseWave® Portfolio system reliably covers the requirements of standard automobile leasing software, the LeaseWave® Fleet fleet management software system allows users to administer value-added, vehicle-related services, such as the management of fuel purchases. Indeed, the fleet management system has the capability to process fuel transactions on both an automated and on a manual basis. Through interfaces with standard fuel vendor files, the auto leasing software has the ability to process large volumes of data in minutes. Each processed fuel transaction is then maintained in the system and the appropriate receivable entries (from the customer) and payable entries (to the fuel vendor) are automatically generated. The customer charge backs can then be billed out as part of regular fleet management services independent of lease-related billings; alternatively, fuel charge backs can be invoiced using the standard automobile leasing software capabilities of the LeaseWave® Portfolio system. The system also provides users with the ability to process fuel purchases manually. This is particularly relevant for exceptional transactions, fuel chits/vouchers, etc.