SF's real estate market is very hot these days. Condos are selling within days. Thus you really need to be ready to move on a purchase when you find the right property.
I suggest you do your homework about areas and then concentrate. There are lofts in areas bordering South Beach which are less expensive.
It's all a function of the space/size and price. There have been some very good deals in South Beach (REO/Short sales) which makes them more attractive as investments. Rent control is another issue so south Beach, because of the age of the buildings, make them better investments than other inner more neighborhoods where more of the real estate is covered under rent control.
I'm happy to talk to you more offline if you wish.
Rich Bennett, Realtor
Zephyr Real Estate