PROBLEM TO BE SOLVED : To efficiently refer to a business negotiation state of other estate agent which treats the same property and to automatically inform a customer of the property of the business negotiation state whenever the business negotiation state changes.SOLUTION : A real estate management server 40 registers business negotiation states by every property shared by respective real estate agents corresponding to a property ID common to respective real estate agents, prioritizes and registers customer information during the business negotiation transmitted from a real estate agent terminal 30 by every property, when there is cancellation by a certain customer, the real estate management server 40 informs other customers of updated priority, when a business negotiation is concluded with a certain customer, the real estate management server 40 informs the customers of the property of conclusion, when desire for tour inspection of a certain customer is received, the real estate management server 40 informs the customers of the property of that, requests transmission of positional information to a tour inspection customer, generates map information including the positional information of the tour inspection customer and transmits the map information to the real estate agent terminal 30.COPYRIGHT : (C)2008, JPO&INPIT