PROBLEM TO BE SOLVED : To provide a highly reliable server device for a real estate auction for performing such large sum transaction as the buying/selling of real estate without any anxiety.SOLUTION : This server device for real estate auction is bi-directionally communicatively connected through a communication line network such as the Internet to a user terminal Y, and the bid of a user in a real estate auction site provided on a network by a server device z or the other server device is permitted or limited, based on qualification retention information showing that qualification preliminarily certified by a financial institute such as a bank is retained by a user.COPYRIGHT : (C)2006, JPO&NCIPI