When I read your "Rules of Trading", I flashed on Butch Cassidy and the Sundance Kid:
Butch: No, No, not yet. Not until me and Harvey get the rules straightened out.
Harvey: Rules? In a comic art trade? No rules! -- after which, Butch immediately kicks him in the...well, you know where.
I've yet to successfully complete a comic art trade. A CAF'er approached me about a cover I picked up a couple of years ago (and, since I don't have a gallery, he had to do some detective work), and he came in with a solid offer. Probably double what I paid in trade value, even if it isn't what I collect. Fortunately, a case of seller's remorse kicked in almost immediately, so our talks didn't go far. Because he was upfront, offered a fair deal, and was generally a good guy, I promised to let him know first if I did decide to sell or trade the piece.