Abstract: A subject property and a corresponding default pool of property sales are determined as a general market for the subject property. Revised property characteristics are submitted to define a new sub-market for the subject property. In connection with this, a map image is displayed depicting the subject property along with properties included and excluded from the sub-market. Functional relationships between selectable property characteristics for the general market and the sub-market are generated, and graphs depicting the same are rendered accordingly. In one example, the distribution of any selectable property characteristic for the general market and the sub-market are concurrently displayed in a graphical image. Interfaces are also provided for individually including and excluding properties from a sub-market.