Based on the information supplied from the end user B, the server 1300a generates simulation information regarding a combination of the elements 100 which can realize the function desired by the end user B in the system 10 and transmits the simulation information to the end user terminal 1100a (S074). At this time, there may be a plurality of users corresponding to the end user B. In this case, a plurality of pieces of simulation information are transmitted from the server 1300a to the end user terminal 1100a. When the function supplied by a combination of the proposed elements 100 satisfies a request, the user referring to the simulation information can purchase the element 100q that he or she does not yet possess. At this time, payment of a price from the end user to the service provider is performed through, for example, a settlement process between the end user terminal 1100 and the server 1300a.