Commercial appraisal The Commercial Appraisal department is responsible for the measuring of new commercial real estate improvements, the updating of existing improved accounts (updating an account would be necessary if the improvement’s condition had changed from the prior year due to damages or remodeling, or due to additions or demolition), and analyzing cost, sales and income data to calculate the market value for each property using mass appraisal principles as of January 1 of each year. The Commercial Appraisal department has many tools available to them for the managing of the improved accounts including specific market reporting websites and aerial photographs (currently flown bi-annually).