I'd keep the collection small while in college. Maybe just the ball python you have already. Unless you could rent a house close to school. Go to college and make the best grades you can and get er done.
On the other hand you could keep a small collection of ball pythons in a rack system without taking up too much space. Ball pythons won't get big like the boa you mentioned. Bp's are also pretty low maintenance. I would check there enclosures everyday to make sure everything is in order, but it would be relatively safe to leave them for a weekend while you go home for some of mom's cooking.
Some turtles and lizards require daily feedings etc.