I +1 Carl's comment, again. I do have some things to add and I missed one thing, too.
RE: Mouthpiece, I was not asked to change my mouthpiece in college ... but that could be because I used one of the same mouthpieces my instructor used. It is possible that your instructor will
strongly recommend that you get a particular mouthpiece, so you might want to wait before buying anything.
The second half of my mouthpiece comment is, "If you're a pro, go with what you like the most." I can say that I'm extremely happy with my Selmer C85, but you may easily like something else (I go into more detail on this subject
here). If it's possible for you to take your horn down to the local music shop to play-test a bunch of mouthpieces, that's probably the best option. The best we can say here is, "I've tried mouthpiece X and I liked it."
The thing I forgot to address is that being a college music major doesn't necessarily mean that you have to go out and get some "professional" horn. I didn't. The best I can say for a professional is that a pro horn is
generally that manufacturer's highest quality instrument. That doesn't mean that one manufacturer's pro model is any better than another manufacturer's intermediate model, or vice-versa. It's another way of saying, "If you played a Bliss (Leblanc student model) for a bunch of years and thought it was neat-o, you'd probably really like the Legacy (Leblanc pro model)." Remember that the clarinet you play is supposed to make your life easier. If you tried a Buffet R13 and prefer your Bundy over that, that's fine with me.