Ask Google what to see in San Francisco and the first one hundred pages will tell you about the ten most popular attractions. Golden Gate Bridge, Alcatraz, Pier 39, Lombard Street, cable cars and so on. That is, you will see only all the most obvious and commonplace. In addition, you are unlikely to really surprise someone with these sights. It's like coming to Los Angeles to watch the Hollywood sign.
It’s much more interesting to be where there’re no crowds of tourists with maps and cameras at the ready. After all, the city is much more than the top 10 places from TripAdvisor - it has a depth and history that can’t be seen in the most typical local destinations.
It would be a great idea to find the cheapest car rental in San Francisco for under 25 and visit some iconic but little-known places in the city. Car is a perfect way of exploring the surrounding area. In addition, you don’t need a lot of money, so that it’s a good solution even for budget travelers.