A user terminal is connected through the Internet to a server. On the basis of the identification information of the client inputted from the client terminal, the server extracts an service selected by the client from a database for user management, further, extracts calculated maintenance contents for each service from a database for service management and sends them to the user terminal. Thus, the user can collect maintenance contents, such as the staff capable of providing service, the time until the user receives a service, and the charge, so that the user can utilize the information as indications to select an optimal service such as maintenance.