i'd like to be able to sort by "not in collection" or by what isn't in there 

Found listing for Final Fantasy VII [Demo] but this name doesn't match what the game is, leading to no price updates because it doesn't match its literal name.
https://www.pricecharting.com/game/playstation/final-fantasy-vii-demo
Should be Final Fantasy VII [Square Soft on Playstation Previews] (or ... VII [Preview] )

Keep track of which games I've played and beaten already

Nascar, Winston card, f1 cards should be added 

There is only neogeo pocket color, but the firts released console was Neogeo Pocket B&W the console has his own games like Neogeo Cup 98 Plus and in color the game is different and of course different price Neogeo Cup 98 Plus Color,

Please fix the case of Dance Dance Revolution ULTRAMIX 4 to match the case of the other 3 as Dance Dance Revolution Ultramix 4

You don’t have any of the promo cards from Pokémon 2022 advent calender

It was pretty important for games as well and has a lot of exclusive stuff on there too. Apple II deserves a spot on this site