PROBLEM TO BE SOLVED : To determine whether a cost is divided by a price or an area for each section by discriminating whether or not the real estate can be transferred when calculating the cost of the real estate that can be divided into a plurality of categories.SOLUTION : In a room-specific cost ratio-calculating processing device 100 for calculating a plurality of saleable selling real estate parts in units of a unit, a storage unit 106 includes a contract master 106a for storing contract information of the sales real estate, a project master 106b for storing the sales price and the area of the sales real estate, and a cost master 106c for setting up the incremental division classification and the transfer target division as a unit for calculating the cost of the sales real estate, and a control unit 102 includes a performance data extraction unit 102a for extracting payment data of the sales real estate, a contract information collection unit 102b for collecting contract information of the sales real estate, a price area information collection unit 102c for collecting sales price information and area information of the sales real estate, and a cost creation unit 102d for proportionally dividing cost for each division on the basis of these pieces of information.SELECTED DRAWING : Figure 1COPYRIGHT : (C)2019, JPO&INPIT