How old do you have to be to be able to become a professional body piercer?

at 18 you can join a school or ask a shop to train you but it does cost to learn most shops will charge you . It is a long process to be able to pierce I've been piercing for 4 years and I'm still learning new stuff . you'll always be learning how to do stuff you need patience, Piercing is not a joke or hobby you have to be in it for the long run or you won't be passionate about it . it is very serious you have to pay attention to who is training you . you wont pierce right off the bat you have to watch an learn first . it is not an easy job but if you love it its the funnest thing in the world . you need a strong stomach and good attitude . don't disrespect old school piercers or artist that's a bad road you don't want to go down .. hope this helps