I think we can facilitate interactions, not sales themselves, and stay within legal realms. That way we stay away from being the interlocutor between two individuals contacting each other and making arrangements; akin to craigslist. We can allow people to list what they'd like or what they have to offer, eh?
I frankly have had some very nice economic transactions with fellow VF people, in manners that have helped my training and involvement in sport significantly. I treasure those interactions, and would love to see us support that. I'd be in support of a listing of needs/wants somewhere.
...I frankly could use an item or two right now...
"The worker has the right to leave his boss, but can she do it? And if she does quit him, is it in order to lead a free life; where she will have no master but herself? No, she leaves to sell herself to another employer. She's driven by the same hunger. Thus the worker's liberty is only a theoretical freedom, lacking any means of realization; an utter falsehood."