Abstract: The present invention concerns an automated vehicle rental system for a fleet of rental vehicles, where the vehicles are geographically distributed and normally locked when not rented. At least one of the vehicles, when not in use, is parked in an unguarded location. The system has a vehicle communications unit for enabling communication to and from the vehicle, user-carried electronic devices, or other readers, and for interfacing with the user. An on-board unit (OBU) is located on each of the vehicles for interfacing with the vehicle communications unit, and with a door unlocking mechanism.