You can choose from 11 categories of rental cars available through Hotwire: economy, compact, mid-size, standard, full-size, premium, luxury, convertible, minivan, sport utility vehicle (SUV), and compact pick-up. Availability at the pick-up locations varies; if the car rental class you booked is not available when you arrive to pick it up, you'll receive an upgrade at no additional charge. (You cannot request a specific make or model -- e.g., a Ford Expedition, a Dodge Neon -- during the Hotwire booking process.)