Parkesquay - this is the law as it stands re HIPs and private sales of residential property:
Properties not being placed on the Open Market � property that is sold by landlords to existing tenants (i.e. right to buy and housing associations), property sold to friends/family etc. that has never been placed on the open market
http://www.hiphiphooray.com/HIP_do_i_need.asp
One has to work within the law, obviously, but this provides a huge roundabout to navigate a course to work it in your favour.