find the neighborhood you like, think is safe, want to be in and walk around. you will see for rent signs everywhere. write down the numbers and go make some calls. that is the only "good" way unless you have someone in SD that you trust that can do this for you, if you are not in SD be prepared to spend a week in a hotel that you can use as a base while you go searching. if you do not speak spanish, make a friend with a desk clerk that can help, for a few pesos on his off hours. let them make the calls. unfurnished also means no stove and no refrigerator.
