PROBLEM TO BE SOLVED : land owner companies and individuals and building owner or asset management and accounting for automatically calculating the numerical value and standard. SOLUTION : real estate companies for accounting for calculating estimated value estimated in a computing system 10, and property information recorded on a recording device and operation information is acquired, and the land area of the building is used in an area ratio of a rental basis for rental opinionated whether it is judged whether or not the present estimated value from a specified time point in future instantaneously in a calculation part 16 is provided, the calculating section 16, and the prices of land and the prices of the building are summed and integrated price, and land based on the profits produced from a building and a profit, is obtained, and in which land opinionated building and when it is determined as to estimate the accumulated neaaly price, land and buildings for lease and when it is determined that an estimated value calculated as a profit. Selected drawing : fig. 1