The issue of self installation becomes a problem when trying to sell the house, the lawyers are becoming sticklers for all the paperwork being available from the original installer I believe a copy of which is lodged with the local BCO so householders cannot claim they "lost" it. Just getting a person to do the gas work does not make it "legal" as there other aspects of boiler installation that need to be signed off on other than gas safety. An example of this is the correct angling of flues for efficient condensing, these can be difficult to check unless done at the point of installation. I suspect very few pro's would sign off other people's work and land themselves in trouble if some time in the future a fault in the installation is found. Even getting a landlords safety check will not be good enough it might show a boiler is safe but not neccesarily that it was installed correctly, a subtle difference maybe. The safety check will not replace the original documents and will only show that on the day it was done the boiler was safe to use.

I have experience of this problem having installed a boiler at my last house getting a so-called pro do the gas work. The lack of original documents caused some problems. In the end we had to indemnify the new owner with a insurance policy which at the end of the day only cost circa £50 against any potential problems and it was condition on that the new owner was happy to accept it.

Richard