An exchange assisting system is provided in an exchange center. Each maker who trades in used goods, such as copying machines, for new ones from a business entity brings goods produced by other makers into the exchange center. The system manages the inventory information of goods delivered from each maker and stored in the exchange center. The system prepares inventory information on goods maker by maker every given period and sends the information to each maker on-line. Each maker prepares list data of goods the maker wants to collect based on the inventory information and sends the list data to the exchange assisting system on-line. The exchange assisting system prepares delivering-out information for delivering goods out of the exchange center based on the desired goods-to-ship data and outputs the information as one needed to ship associated goods to each maker.