I transitioned at 23. The actual physical part of transition was a snap for me. The effects of testosterone were there but not that much of a problem. Kinda like I was always supposed to be this way. The crap I had to deal with from the public was a nightmare. Remember, that was 30 years ago. Being TS was still illegal in many places. I would say that today it is easier for a young TS. There are just so many variables to it all it is hard to say one way or the other.
As for moving to a new town, it is kind of a toss up on that one. I think a lot depends on what you look like. If you are still looking very much like a man in a dress, you are going to look like a man in a dress anyplace you go. If you make a reasonable presentation as a woman you have a 50/50 chance at success.