1. A computer-implemented method for validating a specified price of a subject property, comprising: retrieving a set of real estate properties comparable to the subject property from a case base, the comparable properties and the subject property characterized by a plurality of common attributes each having a respective value; evaluating each attribute value from the set of comparable properties to the same attribute value of the subject property on a fuzzy preference scale indicating desirable and tolerable deviations from an ideal match with the subject property, each evaluation generating a preference vector having a value between 0 and 1; determining a measurement of similarity between each comparable property and the subject property; examining additional attributes characterizing the comparable properties with the subject property; determining differences between the additional attributes characterizing each of the comparable properties and the subject property; applying a plurality of adjustment rules from an adjustment rule database to the differences between each of the comparable properties and the subject property, the plurality of adjustment rules adjusting the price of the comparable properties by either decreasing the price of each comparable property if the comparable property has differences in the additional characteristics that are superior in value to the subject property or increasing the price of each comparable property if the comparable property has differences in additional characteristics that are inferior in value to the subject property; extracting the adjusted comparable properties according to a predetermined threshold; sorting and ranking the adjusted comparable properties according to similarity with the specified price; extracting the sorted and ranked comparable properties; aggregating the extracted comparable properties into an estimate price of the subject property; and comparing the estimate price of the subject property to the specified price and generating a measurement of confidence validating the reliability of the specified sale price.