I will tell you about the two places I know.
Miami, FL. Actually, I disagree with Charles- I think it is very expensive. If you are looking at University of Miami, and want to be in a good area, you will need to pay quite a bit. I am not sure on exact numbers, but Vlad and I have been looking in Ft Lauderdale and we have been finding 1 bdrm apartments for $1200 in good areas, but not even on the beach.
I love Miami and Ft. Lauderdale though (Vlad and I are moving back down in 2 weeks). The weather is very warm, but it is fun! People are always outside and it is just a nice place to be.
Columbus, OH. I live here now. It is a HUGE college city- people eat, breathe, and live Ohio State. I know you are not an undergrad, but the feeling living here could not be more amazing. People are VERY friendly and everyone is always so in love with the school, it just lefts your spirits! The weather is not my favorite. It is gray here, and rains. But honestly, fall is stunning, and spring and summer have beautiful days.
Rent in Columbus is cheap! I rented with three girls, so we had a 3 bedroom big place for $975 a month. That is like dirt cheap, and it was great!
Between Columbus and Miami- I would say I like both, but for different reasons. Columbus is such a great place, very nice people, very family oriented, still big city, but small feel. Miami is very fast paced, many people speak Spanish, expensive, but also very fun.
Hope this helps some!