Megaman Battle Chip Challenge's chips, navis, PETs, prices and compatibility

For Megaman Battle Chip Challenge, several titles in the series use physical cartridges (chips) to boost your character's attack and other stats. Each chip contained a different stat or power, and sometimes even different characters. Each chip was sold separately or obtained through an arcade machine (the latter only available in Japan) and held a different value. They are still sold on ebay or other retailers, so prices can be found online. There are over 400 chips for each generation, three generations in total, so it gets a bit difficult to keep track of all of them.

Additionally, there were PET's that could be used as regular toys and didn't require the videogame, using the same chips and having the same effects, but in real life.

There is a Reddit thread that explains the whole chip stuff better and can be found here.