Two thirds of the purchase price is not common at all. It may be that the surveyor is not accurate (or he is simply unexperienced) or that the property is overpriced.
Normally the purchase price and the valuation figure differ around 10%, at times the valuation being 10% higher that the actual price. What should you do know? You should complain to the bank manager in order to obtain a re-valuation of property. I have done this once and it worked out. And tell them that lower valuations by that amount are not common at all (save the property being grossly overpriced).
