What does it take to become a maintenance engineer? (education, cost of training/education, personality traits, work ethic, etc.)

It depends on what type of maintenance. If you are going into IT System, HVAC, Fire System, Industrial equipment etc. You have to define what industry and I can provide a more defined answer and steps.

If you want to enter the maintenance field, you need to major in mechanical engineering. The cost of training/education vary depending on the university you are going to join and if you have any scholarships. To be a good maintenance engineer need to be good with your hands, patient, and work well under pressure.

Being a maintenance engineer isn't easy. You have to work long and abnormal hours in harsh conditions and you could be called in anytime for an emergency. Having said that, it is lots of fun!