This is a global site. Pinball pricing is far from global. Collecting information is too hard and impossible to normalise. Whatever the posted average price is for a TZ, the global market will still be $3500/$10000 depending on about six different inputs. I love the idea of published price data for any tradable underlying, and it would be cool to see it, but I fear you would spend hundreds of hours trying to build something and find you would not get satisfactory results. The only way you could get anywhere close to collecting good data is if this site actually became a pinball exchange, but then all proper exchanges rely on one unbreakable rule..the underlying asset being exchanged must be a commoditised asset, and pinball machines are, again, pretty freaking far from a commodity. I would sum this up as a great idea that lots of people would like, but is simply impossible to pull off.