An administrator of a system 10 sells an own company's or another company's commodity to a user via a facsimile, telephone, and electronic mail in order to deal with another company's commodity and support and correspond to diversifying customer purchase needs without suffering from inventory. A user information storage device 14 is provided so as to store an amount of payment for a commodity and support, which is determined by a user and dealer, together with user information. A buying-in information storage device 15 is provided so as to store a buying-in price of the commodity and support from a provider thereof. A reception device 11 is provided so as to receive purchase request information from a user 1. A reception processing device 13 is provided so as to consolidate the purchase request information and perform an order acceptance process in accordance with the purchase request information. A commodity transportation instruction device 16 refers to various information stored in the user and buying-in information storage devices 14 and 15 in accordance with the order acceptance process, and instruct the provider to either transport the commodity or provide the support. The provider acts on the instruction by executing transportation or provision to the user 1. The administrator manages and sells an own company's commodity.