Might make a decent wage doing CPL/IR training in the UK, but PPL training should be kept part time if you have and alternative well paid job.
As sole trader/instructor/examiner with a receptionist i can only afford to pay myself the equivalent of £20 hour if i average out my hours.
I could not afford to employ another instructor.
Why do i do it, i can survive and enjoy being my own boss and enjoy the company of folks who want to be there and not clock watching.