rent a car while in the city. It's difficult and expensive to park in the city. Parking may cost you more than car rental. You can always pick up a rental car in the city when you are ready to travel outside the city. I wouldn't stay near the airport. Hotels at the airport are not much cheaper than inside the city. I usually stay in the Fisherman's wharf area, close to many scenic places and more activities in the evening. Hyatt at the Wharf is $109 right now, not bad at all for SF (they may charge you $36 to park your car there). Financial district lodging costs more. Do not recommend civic center area and south of Market - not very good neighborhoods.