An Appraisal is an unbiased estimate of the fair market value of a property and includes recent sales for similar properties, the current condition and the location of the property. Lenders require an appraisal to ensure that the mortgage amount requested is appropriate. 

Appraisals are conducted by licensed professionals who are trained to determine the value of a home fairly, objectively and without bias. The cost for an appraisal is usually covered by the home buyer and, in some cases, by the lender. It's best to inquire. However, the approximate cost would be $300-$500.