You can buy a condo in lots of areas. Just keep an eye on the HOA fee, you'll want to strive for cash flow. East County has really good rental areas, SDSU and UCSD too, but you're definitely not restricted to those areas unless you want to be around a university or medical center. Universities are great for ongoing rental demand, and medical centers will have lots of young professionals looking for rentals. Most kids have cars, but we also have a trolley system, so being near a station could be a bonus for students. There are plans for a trolley station at one of several UCSD locations, but completion won't be for several years.
I can send you listings of properties around SDSU or UCSD or other areas if you'd like, to give you an idea of what's available in your price range. I can also work out your likely monthly payments with current market rents on the listings you like, so you'll know if it cash flows or not. It will help you hone in on an area to buy.
Cory La Scala, REALTOR