The main DIY stores will get around this problem the same way as they get around selling gas fires etc.
Re-market as "BIY stores" buy it yourself.
This covers there arses. They sell youwhat they want and then plaster all over the packaging "only to be installed by a corgi, part p etc etc engineer"
Also if you now ask a plumbing expert in one of these stores for advice now regarding fitting a fire or any other gas product. the fixed reply is "consult a corgi registerd plumber"
the same will happen when you ask an electrical expert how to wire up the security light they have just sold you.
"consult apart p electrical engineer"
that £9.99 security light now cost £209.99

cheers

eggs