I have only just chanced on this topic.
Perhaps I can be a little more positive than some of the others in the middle of this recession.
You have many advantages, age ( because no one likes the texting, drunk, bonking teenagers ), committment, maturity etc.
However your sole disadvantage is that you are based in the sticks! There will be few plumbers in your area and they will be dead scared of even more competition. They already have the problem of a recession and the established competition so they will be acutely aware of the additional problems of training a local competitor.
I took on a mature trainee from 91 miles away although he could stay with his sister so that was OK. He had several problems but had a good attitude in general. However he failed because he was too keen to move towards earning money and left me to try to make a living back at home. He found that difficult because , in his words, every job was a learning experience!
That was about 6-7 years ago and I lost touch but recently, while in the area, tried to find him but have now come to the conclusion that he found the going too hard and has left the plumbing world.
Tony
PS
I hesitate with this! But there is someone ( unidentified for now ) who posts on here in Norwich who badly needs some help with boilers and heating. But he had a bad experience with a useless trainee a year ago which has disenfranchised him from the concept of a trainee ( and future employee ).