looking for a atari 400 rarity/cart list

[Vectorman0]

$20 seems like a good deal for that.

Anyway, the DP guide does have all Atari 8-bit computer cartridges listed under "Atari XE." The rarity and price guides for it are currently being overhauled, but it is still somewhat accurate should give you a good idea of relative rarities and values.

Also, some of the later games from the XE line may not work with the 400 due to higher RAM requirements.