It is very difficult to earn living only with bitcoins.
Firstly, bitcoins are accepted everywhere and you can not pay all your expenses.
Secondly, no legal way is possible to earn that much only with bitcoins.
I love to earn a living with bitcoins in future, but not at a moment, as I am not a full timer on bitcoins, but if I get full time on bitcoins then I would surely earn a living with it.