A system includes: a transmission device provided on a vehicle, for transmitting a signal including a vehicle ID within an area set in advance; a receiving means for receiving the signal; an external control means provided on the vehicle, for receiving a command including an authentication key for a usage right, and for performing vehicle state control including at least unlocking/locking a door of the vehicle from outside a control system inherent in the vehicle; a communication connection means for establishing a communication link to send the command from a user terminal to the external control means; and a management server located on a communication network, for linking and managing the vehicle ID with a status of the usage right.