I've been casually looking for another pin in the $2,000-$2,500 range and seen a few for sale that I might want. But, when I compare the asking price to the pinside estimated value, they are often listed for well over the estimated value listed on pinside (and, we're not talking about collector's quality pins). So, I'm wondering how accurate others find the pinside estimated value to be. I'm not expecting to make a profit on flipping anything. I just don't want to take a significant loss when I eventually sell.

The problem with that is that it shows what people are trying to sell the games for. Not what they actually sell for. I suppose if there are multiple people selling the same game for a similar price, that is some indication, but if every one is negotiated down by a few hundred dollars before the sale, it is not captured.

How do you get completed sales data?

That's a great chart and seems to show what I've been noticing, that these ~$2,500 pins are starting to increase in price substantially. At least if the Pinside average price is lagging behind by a year or more.