An overview of car hire rules 1 through 4 and rule 25. Rule 1 deals with the registration of cars in the Umler system and car hire rates. Rule 2 governs the calculation of hours and mileage. Rule 3 covers the reporting and settlement of car hire. Rule 4 allows relief from car hire for empty cars that are moved under revenue billing. Rule 25 outlines the arbitration procedure when agreement on car hire rates cannot be reached.