A survey of NAEA members shows of those 10 per cent, 46 per cent have seen a drop in excess of 30 per cent.
NAEA Chief Executive Peter Bolton King says the figures show that there is an anomaly between instructions on properties where a Hip is required and where one is not.
He says: “I have heard of many examples where potential sellers have decided against putting their property up for sale because they do not want to risk wasting £300 or indeed much more, if they decide not to sell.”
Seventy-six per cent of respondents to the survey also feel that Hips should be scrapped altogether and Energy Performance Certificates should instead apply to all properties.
Bolton King says: “Despite the fact that agents have now had an opportunity to work with Hips it is clear that the vast majority of respondents do not believe that they add value to the process and are finding it hard to get purchasers to take interest in them. We feel very sorry for the many domestic energy assessors who are waiting for the opportunity to earn a living.
“As a result we again call on the Government to take into account the above evidence and to reflect on the potential increased damage to the market if they roll Hips out across all properties. We would urge the Government to take the opportunity to review the situation and find a quick way of enabling the Energy Performance Certificates to be applied to all properties without the need for a Hip.”