Going to school in Boston (BU)

Boston University is definitely my top choice but before I commit I have general questions about the school and going to school in Boston overall.

-I did not receive any scholarships or grants, but my family has money saved aside that could put me through undergrad, but I’d still have to take out some loans. I definitely want to go to grad school. Other than loans, how else can I pay for BU and make the cost more manageable since I want to go to grad school afterwards?
-with so many schools in Boston, how easy is it to connect with students from other schools in the city (Northeastern, BC, etc.)?
-I’m going to be a science major, but I’m still undecided in the long run. How difficult are the “weed out” classes and how bad is grade deflation? I don’t want to spend so much at BU just to graduate with a low GPA that would hurt my chances of getting into a good grad school, but I’m willing to work hard.
-How helpful is BU with finding work or internships after/during college?

If anyone can answer any of these questions that would be great, thanks!

How much in loans?
What are your other options for college?
Other than some small outside scholarships you can apply for there is no other aid.
What type of grad school? Medical school? Ph.D. program?

I was accepted to my state school which will be less expensive but not as many good opportunities and the departments I want to be in are not as strong as BU’s. I’m looking to med school for now but I’m still pretty undecided and will probably change my major so it’s not for sure.

What do you mean by “weed out” classes? BTW going to BU for the Boston-London program.