Working at 18 in JP?

Hiya

I was wondering if its really hard to work in Japan when your 18? im asking because I live in UK and Id like to take a gap year before university, but im not sure if there are much people willing to employ someone at 18 years old. I know you can only teach english at 21, not too sure about being an assistant.Im hoping to move to Tokyo

Thanks

The only visa that is viable in your case is the working holiday visa, assuming you are a UK citizen:
http://www.japan-guide.com/e/e2350.html

If you are a native English speaker and have good social skills, you should have little problems finding customers as a language tutor.