PURPOSE : A business mode for operating an apartment price/transaction information site is provided to promote the qualitative growth of a real estate information offering site by reducing thoughtless diffusion probability of real estate information from an initial stage that the real estate is entered and maximizing reliability of the information with a monitoring function of final information users.CONSTITUTION : Information on Apartment trade, deposit base lease, monthly rent collected from a realtor of each apartment complex is transmitted to a central server. The apartment information is stored/managed by each region/date/feature/realtor and other rules, and is provided to users accessed to the central server. When the apartment information registered the realtor is changed, the corresponding realtor modifies and removes the apartment information without delay. The modified/removed apartment information is reflected to the central server. The monitoring function is added by installing a mailing system in addition to a bulletin board or a reply function.? KIPO 2006