To provide the information relating to the possibility of mounting an optional component to a vehicle, to user.

An information center refers a storage device on the basis of the identification information acquired from a user terminal for specifying a user or a vehicle and the identification information on an optional component desired to be mounted on the vehicle, as a retrieval key to acquire the information relating to the three-dimensional shape of the specified vehicle corresponding to the identification information and the information relating to the three- dimensional shape of the specified optional component, and judges the possibility of mounting the specified optional component to the specified vehicle. The screen information displaying a result of judgment is provided to the user terminal.