It's not 1982....cell phones are loaded with minutes, and anyone making a decent amount of phone calls for business purposes will just get unlimited minutes.
I think it would make more sense to have calls be free but have a limit of say 50 calls each recruiting period....just to throw a number out there. It would allow you to see if you were a back up, out of your league, etc without having to throw money away and it would also make it a bit more realistic.