Real estate appraisal, property valuation or land valuation is the process of finding a property's market value. Appraisals are needed because compared to, say, corporate stock, real estate transactions occur very infrequently. Not only that, but every property is different from the next, a factor that doesn't affect assets like corporate stock. Furthermore, all properties differ from each other in their location - which is an important factor in their value. Due to a lack of frequent trading, qualified appraisers are needed to advise on the value of a property. The appraiser usually provides a written report on this value to his or her client. These reports are used as the basis for mortgage loans and to set the sale price of the property appraised.