PROBLEM TO BE SOLVED : To solve the following problem : in a conventional real estate transaction system on the Internet, Web sites are often managed by real estate agents, inexpensive properties are sometimes false property information just for the purpose of attracting a user to the site and estate agents, they often do not actually exist, so that it is extremely difficult for a customer to decide whether or not the property information on the Web site is real information. SOLUTION : In the system, direct transaction is performed between an owner of the real estate property and the customer. By comparing owned property information to be inputted by the owner to an owner terminal 0102 with authentic property information in a real estate transaction management apparatus 0101, only the property information which is confirmed to be actually exist can be provided for the customer who operates a customer terminal 0103, so that a lure advertisement can be eliminated. COPYRIGHT : (C)2007, JPO&INPIT