The type of appraisal you want to have done will be one of the factors in determining the overall cost of the appraisal. There are different types of appraisals that you can get, but the most common appraisal is the URAR or the Uniform Residential Appraisal Report. There are shorter appraisals that can be done, affectionately known as "Drive By" appraisals. The shorter appraisals will cost less but not all lenders or banks will accept them as full appraisals. Check with your lender or real estate agent as to which kind of appraisal is best for your needs.
The value of your home will also be a factor in the price of your appraisal. Technically this is what you are having appraised, but homes that are of a very high value will cost much more to appraise than homes that are lower in value. One of the "cut offs" for the price of appraisal is five hundred thousand dollars. That means if your home is worth more than five hundred thousand dollars it will cost more to appraise than a home that is worth less than that.
The kind of property you have and what you use it for are also taken into consideration when determining the price of the appraisal. Typically single unit family homes and condominiums that are only used for you and your family are less to appraise than single family homes or condos that are being rented out for a profit. Residences that are used to make a profit (like multi-family rental units) will have appraisals that cost more to complete.