Is this an estate agent or a mortgage company valuer?
If its a mortgage one then all he's interested in is ensuring that any mortgage taken on the property is covered by the value of the house - ie as long as the mortgage is less than the house value, then he's happy.
They also produce a cost involved in rebuilding the house if it needed completely rebuilding - this cost will be considerably less than the house "market" value.
If its an estate agent, then he's looking at a realistic sell price for the house, and don't forget that if he's keen to sell it, he may value it low just to get it through his books quickly - for the difference he'd lose in % - he'd rather sell it quick and cheaper than at top price and take a while - the longer its on his books the more it costs him (advertising etc).
Tim
