Do not take a RV on 101 through SF. Golden Gate, 19th Ave/US1 to 280 is very doable with a RV. South bound the exit (right) to 19th ave is very short. Stay in the center lane on 19th Ave when 3 lanes are available. Avoid rush hour.
North bound no bridge toll. South bound has a toll but no toll collectors and you DO NOT STOP. Pre or post pay. Locals have a FasTrak device. Not sure if S CA devices work.
Since the toll is based on the number of axles suggest you get online a few days later and pay. DO NOT IGNORE the toll as they will bill you and fines start if you don't pay in a few weeks. It's your problem if you're not home to get the bill. Google FasTrak.
For SFO with a car I'd take 280 to 380. But the SF bay tourist area is east of 101.