Eddie,
Some of the rules are about disputes if the item is not as advertised, and difficult or expensive to return etc.
Also it would be hard to take somebody to court living in another Country.
Have you ever sold on Gumtree around your local area, or wider. I have just sold, lots of stuff on there.
And if anybody is interested, I have 3 framed prints, 45cm x 55cm of historic world speed records, of 'The Mallard', Cunard Liner 'Blue Riband' & a 'Suberplane'.
All can be seen on Gumtree, in the Newmarket area :-)