I can't quite figure out his deal, but guess he has something of a hoarder mentality, is slightly greedy/wants absolute top dollar and is emotionally attached to his giant stash.
I've had a deal banged out twice on one of his items -price hashed out, meeting place, day-, but when the fateful day comes, he doesn;t answer his phone or respond to emails. It is totally aggravating, yet I'll likely give it one more shot here in the future... I'm a glutton for punishment!