Well Martin W apparently feels that we should have allowed the mirror to be sold at less than 15 posts but the engine should require more than 15. As it stands, we have a rule and we are consistently enforcing it.
Opinions on whats right appears to be polarized, with very different views. I think I glanced over the new very prominent paragraph (50 posts) in the 350z for sale section without realizing it was specifically related to the car, so sorry for that!
But I also happen to believe that if you're trying to put off people who only join so they can sell, that 15 posts by itself is a nonsense. This could be achieved in a couple of days without raising suspicion, merely by asking reasonably intelligent questions.
It was suggested by someone else that a number of posts over a qualifying period would be a better approach. IMHO I agree with that. But I also wonder if its worth the effort of policing this if there isn't a major problem.
Dunno, a difficult one...