I would repeat don't worry about.
If you are going to look and consider every bit of legislation to that extent you will never get anywhere.
There are some that are serious - proper health and saftey issues - and some that really will not cause you any problems if you ignore them. IMHO.
First port of call if any problems will be to just warn you - but I bet you never ever get this even.
Just get on with it.
Heya
Have to say I am with you on some of this and not with you and I will outline some of my thinking. Firstly though I have to warn that I may wander off-point and this is just me being discursive it isn't meant to be offensive.
To begin there is far too much legislation in effect that is true. Much of this legislation is counter-productive to business and it would seem to common sense also. So a reduction in the number of legal requirements of a non-destructive (in which I mean damaging to people, place or rights) nature would be a good thing. I am in favour of that as I am in business.
But the reason we have so many of these -minor- and difficult to enforce pieces of legislation is because of responsibility. I personally believe that businesses should try to be as open and responsible in their dealings with clients as is possible. Unfortunately many people do not believe the same. If they could, many businesses would not give their full details out and would hide or shroud their activities from scrutiny, consider the manner in which the farmers were treated by the supermarkets in regards to the price fixing of milk and cheese.
So we have to write these things into law, and because there are so many people with little responsibility who have to be brought to account we end up writing more and more items into law. This is to protect the rights of people, which in turn creates more paperwork, and puts us as businesses into positions where we must pick and choose what responsibilities we take and which ones we ignore.
some that really will not cause you any problems if you ignore them. First port of call if any problems will be to just warn you - but I bet you never ever get this even. Just get on with it.
In this regard, this attitude, which is common, and one I have found myself using when I come across pointless legislative issues is in fact part of the problem as it encourages the behaviour that results not only in more legislation but in more heavy-handed enforcement of that legislation (which is worse).
My main point is still responsibility. If we act responsibly then we would have no need for these forms of rules. There are far too many bogus companies, or fronts or flash-in-the-pan people out there trying to con the public and the only way we can instill trust in the public is by behaving responsibly. If we all did this then we could be justified in asking for a reduction in the need for so much red tape.
The reason I pointed at the government links was to indicate the legal nature of the overall argument as this was the general nature of the original question. My opinion was and is that we should not deal with people who do not use contact addresses. I would not trade with someone who I could not pursue in the event of a serious breach or dispute and I think it is dubious to have no contact details on your website if you are trading. If you want that level of anonymity sell yourself on ebay.
Sorry for sounding off on this

I will put my rant away now and leave the box for the next lunatic on speaker's corner
