A common misconception about appraising is that appraisers rely on a basic cost per square foot dollar amount when estimating values.  This is not the case.  Real estate values and real estate appraisals are most impacted by location, construction quality, age of the improvements, and condition of the improvements.  Lot size/value also comes into play in most cases.  Appraisers consider all of these factors when analyzing properties and make every effort to compare the property appraised to sales of properties that share as many attributes with the subject property as possible.  This reduces the number of adjustments in the report and typically results in the most accurate appraisals.