Go by the rareness of the chip and the fact that as teenagers we probably don't have THAT much money to blow on chips xD 

So let's say 20 basic chips. And 4 rare chips. That seems about fair right?

Also keep in mind, no boss chips. Like in the games you got chips after beating bosses and others navi. Not in the RP. Other than that chips are pretty fair game. And we'll get more as the RP progresses.