I'm from Atlanta, and I just spent a week in Charleston on vacation, and by god if I had reason to move there I would. That city is beautiful! I remember thinking what a great place it would have been to go to college. In comparison I think Atlanta is kind of dirty and boring and too difficult to get anywhere without a car.
I wouldn't listen to the name brand gate-keepers...name brand can help but it by no means determines your ability to get into somewhere like MIT. It is not very important for undergrad; grad school is where it seems to "raise the glass ceiling" as far as future career options, but there are of course always exceptions.
Its definitely not worth paying 40,000/year just to go to a school that's "well known" when you can get a perfectly good education in Charleston, paying maybe $40,000 for your entire 4-5 year stay and possibly getting state scholarships. On top of that, when I went to Georgia Tech to get some prerequisite courses done, I noticed that there is a strong "grade deflation" culture there. I.e., many professors will give impossible tests where the class averages in the 40s and then they will "curve" it up so that they can get their nice bell curve required by the department. In my opinion this is fraud, it is not representative of students' true ability and it encourages unnecessary and sometimes cutthroat competition among students in an environment that should be conducive to learning and academic success.
In my undergrad, I went to an unranked school in mathematics that no one outside of my state can even pronounce let alone has heard of, and for grad school I got into the number 3 school in the US for nuclear engineering, and I won an international fellowship to study for free in the UK for a year.
Not that I'm tooting my own horn...I'm just saying that undergraduate education is what you make of it. For any given degree program, you are going to "be taught" more or less the same material whether you are at Harvard or West Virginia State. What one actually "learns" depends on one's motivation and persistence in seeking out opportunities that will lead one to success in graduate school (for example research internships, REU's, graduate courses, directed study, research with a professor at the home university).
Getting into a top school basically comes down to grades, GRE scores, letters of Rec, personal statement, and research history (coupled with letters of rec). You can get all of these things excellently at a smaller school if you play your cards right and put in effort. An outstanding letter of rec from an unknown professor is better than a bland one from a superstar. That's not to say they will be handed to you at Princeton or MIT, there it will take the same amount or more work because you will be competing with other so-called "genius" grad-school bound students for the same resources. Getting a 4.0 at Charleston would look much better than a 2.8 at GT.
PS: If your son is willing, he could stay at home while in college. That saves a tremendous amount of money over the long haul. I was able to graduate debt-free by staying home and working while in school. Even if he only did it the first two years, it would make a huge difference for your wallet.