I auctioned a group of lightly used, and I do mean lightly, Athearn BB Geeps, GP35's, 38's and a few GP9's, on eBay not too long ago. The bidders were nuts!!! One NW GP9, lightly, yet nicely, weathered and detailed went for $79 plus $7.50 shipping!! I figured if I got $25 each, I'd be happy. I was truly shocked!! Not, shocked enough to offer a refund though. I started the Started them low to get a bit of action. engines at $12.99 plus shipping.
The train market is really weird on eBay lately. High quality brass is going for a pittance many times, while pieces of crap are really commanding higher prices. Really odd, IMO.
Bob