I was in the Corps and highly recommend it.
New corps members do not have to pay for uniforms. They are issued. I think if you go D&C your junior and senior years there is some charge, but it's not very expensive.
Fees above and beyond non-reg fees... not really. You ARE required to be on a full meal plan (unless that's changed), because the entire Corps marches into the mess hall for chow twice a day. You ARE required to get a sports pass (I think football only) because the Corps marches in to football games, and cadets are required to attend.
Fish may have autos. They are not restricted to campus, and may leave when they want. To leave campus in uniform, cadets must be in class B uniform or better. Cadets may leave in civilian clothes. Keep in mind: They will not have a lot of time to leave campus during the week, except for things like going to the cleaners, barber shop, doing laundry, etc. All those services may also be found on campus. There will be some weekends where outfit activities keep them on campus. I recommend getting on the list for a southside or Koldus garage spot if leaving campus is important.
Corps students may take as few as 12 hours, or as many as they want. Fish should start slowly until they get the hang of college and of the Corps.
Bull text will not be a problem. Those classes don't take up much time, particularly in the first couple of years. They meet once or twice a week, plus some sort of lab once a week, and an FTX or two per semester. Labs and FTXs are incorporated into Corps activities. These classes require learning some skills, but very little reading, and the testing, if any, is simple.
Some cadets graduate in 4 years. Most don't. The extra classes don't have anything to do with it. The time commitment of the Corps might have something to do with it. However, most students don't graduate in 4 years anymore, cadet or not.
Folks can visit cadets in the summertime. For that matter, lots of people visit on weekends during the year. During the summer, the corps "dies." Some cadets are on campus, of course, and some cadet activities go on. These usually involve the leadership of the Corps, special units, or recruiting. But most of the day to day "Corps games" cease, the Corps effectively vacates the dorms, the Corps does not form or drill. Cadets do not have to be in uniform unless they are participating in the above-mentioned activities. Many cadets live in other dorms or off campus in the summer.
I hope this adequately answers your questions. Call the Corps and get it straight from the horse's mouth. Things might have changed.
My advice to the young man:
1. Join.
2. If you think it's too tough, hang in there. You can do more than you think you can, and you'll be glad you did.
3. If you hang in there for a while and you still want out, get the hell out. Don't hang around and cry and ruin it for the rest of the Corps.