In reply to kipper12:
Who's saying that, the buyer? If you can take the slight risk of them pulling out, call their bluff. It's all over the place in most houses, and it really isn't a problem if managed properly. If it's the agent, find a new one, they are meant to be working for you, not the other way round.
You really *do not* need to get it tested nor removed.
By the way, why have you had a survey done for the *sale*? You appear to be in England. In England, the surveys are the responsibility of the buyer, so you needn't have wasted your money.
Edit: Do you just mean a valuation?
Post edited at 22:35