Many home buyers make the mistakenly think that the HUD or FHA appraiser is doing a Home Inspection of the property they are buying. The appraiser is there to establish that if the house is repossessed, the bank will be able to recoup all or most of its money.
An appraisal is not a Home Inspection, and the appraiser is not a substitute for a Home Inspector who goes through the complete house, inspecting all the various systems and components for defects and safety.
The Home Inspector works for you and has your best interests at heart during the Inspection.
The appraiser works for the lending institution, not the home buyer. (Yes, you pay for the appraisal) He is not interested in the fact that certain things do not work, or that you could have problems after you move in. His job is to check that minimum housing standards are met, and that the house meets the description of what the bank is lending money on.
NOTE: HUD and FHA forms state that their appraisal is not a substitute for a Home Inspection.