Abstract: An assistance system assisting communication between a supplier providing an article-related service requiring work for an article and a user demanding provision thereof, has: an acquisition unit acquiring three-dimensional model data of the article based on a user instruction; an article presentation unit presenting one of the user and supplier with an article screen expressing the article observed from a predetermined viewpoint, based on the three-dimensional model data; an annotation data generation unit generating annotation data for displaying an annotation screen obtained by writing annotation information on the presented article screen so as to include viewpoint information specifying the viewpoint; an annotation data acquisition unit acquiring the generated annotation data; and an annotation presentation unit presenting another of the user and supplier with the annotation screen based on the acquired annotation data from a viewpoint corresponding to the viewpoint information of the annotation data.

Abstract: A transaction assistance system determining a provision requirement for providing a service, to assist closing a transaction has: a service setting unit setting, in association with service information of each service used in relation to selection of the service, a service candidate group including services providable to the user; an information item setting unit setting, for each service in the service candidate group, an information item necessary for the supplier for determining the provision requirement; a service selection unit selecting the service provided in response to a user demand from the service candidate group using the service information and selection information acquired based on a user instruction; a request acquiring unit acquiring, based on a user instruction, request information for specifying a request by the user for the information item; and a determining unit determining the provision requirement based on the request information.