I've taught off and on just for the fun of it -- Random weirdness I don't understand fully: I've offered to teach for free, get less turnout than when I charge absurd amounts.
Anyway, don't think I'd be willing to make a job of it -- Unreliable, and I'm getting older-ish and my body doesn't hold up too well, anymore. Started with Hapkido around 8 years old, went from there into Chuan Fah/Kenpo, from there into Muay Thai, off into Brazilian JJ, then ended up on Filipino MA which became and remains my fave. Not so much the stabbing things aspect as Panantukan.