To provide an estimate information exchange system capable of reducing the required cost, labor, and a period by using the Internet instead of a conventionally performed telephone, mail, facsimile or carrying-in from a request for an estimate, presentation of the estimate, and up to a determination of an estimate amount between a general contractor company and its cooperative companys in the construction business world.

Preparation of a written estimate request, the transmission of estimate request mail, preparation of a detailed estimate statement, and estimate preparation return mail are executed via a Web server existing on the Internet communication network between the general contractor company and the cooperative companys. Estimate information is mutually exchanged between the general contractor company and the cooperative companys.