Most car rental offices offer arrange of vehicle sizes to suit a variety of budgets and space requirements and some additionally offer specialised vehicles to suit its location such as convertibles, prestige models, hybrid/electric vehicles or SUVs and passenger vans. At major airports or in larger cities, some independent car rental agencies offer high-end vehicles for rent. Some specialised companies such as Rent-a-Wreck offer older vehicles at reduced prices.

To allow for a uniform classification and easy comparison of car rental prices, the Association of Car Rental Industry Systems and Standards (ACRISS) has developed the ACRISS Car Classification Code coding system. This describes the size, door count, gearbox type (manual/automatic) and whether the car is air-conditioned, encoded into four letters. Additional classifications based on seat numbers and trunk volume were also set by the Belgian Rent a Car association in order to provide a unified system for assessing the car types in online reservation systems such as Amadeus or Argus.