Braces can cost a pretty penny, especially if your dentist has you come in every month for check up, maintenance, and changing the rubber bands.
The length you wear them is determined by the "problem" in your mouth (for a lack of a better way of saying it) and what your doctor recommends. I had braces two times during my life. The first time was to correct crooked teeth and I wore them for about two years and then had them removed. A year later my wisdom teeth screwed up some teeth coming in so I had the wisdom teeth removed and had braces put in on only one side of my mouth where the problem was. My second round was only for a year.
What is worse if they have you wear "head gear" which helps correct things like overbite, etc. Such a dinosaur way of dental health. Unsightly and uncomfortable. Been awhile since I experienced that so I don't know if its even in practice anymore. If it is, it might just be easier to have the teeth pulled.
Can't really recommend anyone considering I currently do not live in the DC area but the dentist will probably recommend you to a specialist or orthodontist. Good luck.