K, Katarina, here is the scoop. An appraisers opinion is based in large part for whom he is doing the appraisal. When an appraiser does an appraisal for a bank, he is trying to justify the sales price to the bank, in other words he is there to show the bank they are getting value for the money they are loaning. Very seldom will you see an appraisal in a loan situation come back more than the sales price on the purchase contract. Some times less, especially in this market, but never more (ok, maybe a thousand or 2, but if you are buying a home for 160,000 and you think it should come back at 200,000...it won't happen because that causes a red flag with the lender!) You also run the risk that the appraiser you choose may not know the local market or the neighborhood, and may not give you accurate information.
So, if you are looking for a value on your home just to know what it is, a market evaluation or a CMA (competitive market analysis) is a better determination of value. Realtors look at what homes have sold for in the area, what homes are for sale (your competition should you decide to put it on the market), what homes have expired (not sold when they were on the market), conditions of the homes, and they analyze all this data to determine a trend for the neighborhood. They will also be knowledgeable about the Local market (where all things Real Estate happen) and even the neighborhood you live in so they can give you a more accurate information.
Now, if you are just looking for a general value, here is a link to get a market snapshot that will keep you informed of what is going on in your neighborhood and the area around you...no obligation, just good information. http://www.homeinsight.com/Widget/default.asp?XPBPHTLVR8M3
As always, let me know if you have questions!