BECAUSE pictures weren't common, it was hard to start a new life. If you were an adult and knew no one in the town you arrived at, no one would trust you, give you a job or rent out a room to you. Cause they'd all assume there was a good reason you ran away from the place where people knew you, and there was no way to verify if you were who you claimed to be.

Ummm, people moved all the time. There wouldn't be a reason to assume you were running from something. Have you never read a history book? You could even just be moving to a smaller town in the country side for "fresher air" to help your tuberculosis.

If you had a profession, you needed a letter of recommendation from your former employer or your guild to vouch for you.

Depends on the job, how much starting money you had, and where you're moving too. You could for example say you're moving to set up a chemist shop, especially in the smaller or more remote towns.