It's fine to rotate pins. People do it all the time. The problem is losing cash on each NIB purchase. You'd think it's "only a couple hundred dollars" but it adds up. I'd set a budget, of say $5K, on a machine, maybe in its own account. Then use that cash to B/S/T. Buy smart and you should be able to break even, or even gain some profit on MOST transactions. That will certainly keep you of the NIB market however, but the good thing is that there are plenty of games excellent games that are 20+ yrs old.