The present invention refers to real estate trading of commercial and leasing method relates to, such, real estate via the Internet deal and lease contract mediation method (a) the user to be rental or selling real estate number 1 by an operator using the user' s computer to a server site position of article and the, aren' t, unit extracts, site to retrieve a buying information ; (b) said input estate information with a local, kind, price, aren' t estate said classification by the classification that is responsible for the area of a cell end and real estate broker or real estate intermediating agent with, storing said database of said server ; (c) said classification by estate information computer intermediating agent or broker area and transmitting at least ; (d) said user be leasing or filling a real estate number 2 by an operator using the user' s computer to a server position of real estate site, said by considering site to retrieve a buying real estate broker or selects a single or a plurality in real estate, said selected real estate intermediating agent to estate broker or such as visited-in-place a predetermined preparing a fingerprint for contract; and (e) said floating for a contract for trading or lease [...] comprising characterized in that.