So many questions, but I kinda expected that at the outset of this thread.
Yes, on several occasions a bona fide COLLECTOR has unloaded or partially unloaded his collection at the store. People really do "get out of this", priorities change and on a number of occasions I've heard "I'm keeping the few games I play, everything else must go".
That's gonna take some serious time to think about. We're open over two years now. Part of what makes me want to document this year is because so much of the last two years is lost in my memory. Plus this would make a great chapter to that book I'm going to write someday.
It's a combination of things. For most current get stuff it's a percentage of the resale value. For older stuff it's flat based on condition, completeness, and quality of title. For the very high quality stuff we present what we think will be a fair price. All of this is kept on spreadsheets in our store's computer. I don't get a lot of complaints about our values, often people share with us how much less GameStop had offered them just before they took it to us.
I have a blog on MySpace (see link below) that touched on this. It has only happened once. I've discovered people who do that are really rude, so I'm equally rude if I see it starting to happen. There's a deal on the table, they can wait until that deal is settled to negotiate their own deal. By that time it is most likely property of the store.
I should also add that although this forum community immediately knows the value of something like 32X Web of Fire, the average customer has no idea and often no interest in it. The likelihood of one of us hardcores being in the store at the exact moment someone was trading in something like that is extremely low. It's the common stuff that everyone is looking for that is usually "sabotaged". Tyson for the NES is a perfect example of that.
I've given this a lot of thought and there are only two reasons for me to put the store online. 1) people aren't coming in and buying stuff or 2) there is too much overstock to manage. I do have an eBay store but I add to it in spurts. That could change as time permits.
Not very often, but sometimes I've taken them anyway if it's something I deem useful to a friend, family member, or myself. I've bought a few cheap iPods and own two portable DVD players.