When an appraiser values your property for financing or other purposes, you usually receive an appraisal consisting of three or more sales that estimate the value. The scope of work is for an individual property. This is a single property or fee appraisal. Single property appraisals are not financially or logistically feasible for tax assessment purposes.
Mass appraisal is defined by the International Association of Assessing Officers (IAAO) as “the process of valuing a group of properties as of a given date, using standard methods, employing common data, and allowing for statistical testing”. It involves analyzing data collected in mass quantities, developing statistics from the data, and applying the results to large numbers of properties. The mass appraisal method is used for tax assessment purposes and is necessary to accomplish the assessment of the thousands of parcels within a locality.