I personally use eBay's Completed Listings option when I price pinball machines. You can see every one of the overpriced games there with the prices in red. The only prices that mean ANYTHING are the ones in green. That would be what the buyer actually paid at auction/bin close. There's the occasional "I really wanted that Hurricane so I paid $2500" auctions but most of them reflect the real world.

I chuckle sometimes when I see games listed here for more than they're worth especially when there's a multitude of "great price" follow-ups. But sometimes you just gotta have THAT game so you pay.