I think that paypal's buyer protection on the goods/services buying option is a way to instill some confidence in a buyer. If the seller refuses to accept goods/services than I take the extra 3.5% or so of pp's charges for the seller. If the seller STILL refuses to accept the commercial payment I start getting very selective. Only when the seller has a track record of good conduct I will buy from him. Once I had more than one successful transaction I will gladly go to friends/family. Never had a bad transaction that way.
While it may be possible to make the commercial transaction mandatory, as forum operator I wouldn't go there. The only safe way for him is to strictly keep out of any legal involvement in forum member's dealings.
Well, in the end every one is responsible for his actions and any consequences thereof. When I'm buying from a forum member I will always check:
- date of registration
- number of posts
- number of racks
- accounts on other forums
- other traces of activity on the internets
If all that amounts to a profile of a well behaved active netizen with a good reputation all around I will buy.
If it doesn't I will move on. While no single item on the list is a a reliable indicator, all of them will tell me.
In other words, if I buy without protection from a member who registered just shortly, with no references to other internet activities, has made 0 posts, rated 0 modules, has 1 empty rack but a dozen modules on offer for cheap --- I'm probably very stupid.