Nearly all houses that are marketed require a HIPS. There are a few exceptions but these wont affect most people. Houses being sold through an auction will require HIPS.
This surely will take a lot of the gamble out of buying at Auction, and with the certainty prices will rise poss.
Although if all defects are stated, without being rectified, and the house bought in that defined state, then that is the gamble.
Anyone bidding at auction always had the opportunity to check out the condition of the offered lot - at their own expense - beforehand. So the only thing that has changed is that the vendor has to provide the info upfront. I've been to auctions in the past where the legal searches part of the HIPs pack has been provided by the vendor.
Hard@it, I think the parts of the HIPS that you refer to concerning defects etc in properties are only optional anyway and so, in many cases, these wont be included.
The only compulsory parts are:
An Energy Performance Certificate
Sale statement
Standard searches
Evidence of title
Home Information Pack Index (!)
You would need to have your own survey done to be sure of any defects.