Qualifications
There are some people who have a knack for mechanics or electricity. If you are one of these lucky people, we have a couple pieces of advice: take advantage of your gift; and be careful about giving out your phone number―you'll have lots of friends who'll want you to fix their stuff.
If you're one of those fortunate enough to easily understand mechanics and electricity, then an apprenticeship might be a good option for you. These programs are often run by unions, such as the International Brotherhood of Electrical Workers (IBEW) or the National Elevator Industry Educational Program (NEIEP) (source).
You can apply for an apprenticeship at any time, but first you must pass an aptitude test to be considered for an opening. There are several unions to which elevator installation and repair technicians may belong, and the costs and other details for their programs are only available to members. Our best advice is to look for open apprenticeships in a city where you'd like to live, then work through the union involved.
There are also some college programs designed especially for this career, many of which will accept some of your apprenticeship credits toward your associate's degree. The costs for programs at community colleges or vocational schools usually vary from about $160 to $520 per credit hour (source).
Either option will grant you the knowledge needed to get your foot in the door, so it's up to you to recognize whether you learn best by doing or by studying.