If you mean by "unfair", that the appraisal is either too high or too low, there are several things you can do. The first is to talk with a real estate broker who can provide you with comparable sales data. The most important part of the appraisal process is the analysis of comparable sales. The appraiser also looks at rental potential and at replacement costs, but, since buyers and sellers determine market value, the "comps" are of unmost importance and are weighte\ed more heavily in the final figure than the other two analyses. Your appraiser may have chosen the wrong comps either because s/he has a limited data base or is not on top of the market. That's where the real estate broker can fill in any gaps in the appraiser's analysis. It is good to remember that an appraisal is a look into the past and not into the future. In a time of falling values, the appraisal may be too high for the market and your real estate broker can give you insights into that aspect of the market. You can also talk with the appraiser and determine how s/he came up with the value that s/he did. If you know of some better comparable sales, you can ask why those were not used. Remember, an appraisal is one person's opinion and we all look at things differently. I hope this helps.