It's good that you're asking all these questions.. good for you!

Burms are a huge commitment.. they can live over 20 years as well as grow to be huge. Male burms can top 13'.. I have a picture of one on my computer which is 15' and 100lbs.. and yes, it's a male. That's a lot of snake.

A couple of things to keep in mind..

Once the snake is over 8' or so you're going to want to have a helper with you whenever you have that cage door open. Better safe than sorry, it's just not safe to handle a big burm by yourself. Do you have someone willing to do that with you?

Secondly.. what are you going to do with the snake if you go to college? Think ahead.. big burms are hard to find homes for, they fill the reptile rescues.

Best of luck with whatever you choose.