Hi. Check out sdreader.com and sandiego.craigslist.com to see how much it costs to live and what’s going on. A great resource for you would be couchsurfing.com. Sign up and then contact people who live in San Diego – they will be very helpful.
I’d recommend Pacific Beach (aka PB) to live if you like the beach and fun people in their 20’s and 30’s.
University of San Diego – Catholic School – extremely expensive – difficult to get in.
University of California, San Diego (UCSD) Great school for sciences. Difficult to get in.
San Diego State University (SDSU) – large public university. 10 miles from the beach. Great business school. Easier to get accepted.
I think all three schools have an “extension program” which you just pay to take classes and don’t have to be accepted formally.
You can do the extension program or community college and then transfer into a program (major) if you want to graduate with a degree.
Hope that helps.
BTW – if you like good weather and the outdoors there is no better place.