Just look for directions to the SFO Airtrain - there's escalators that take you up to level 3 and a walkway over. It is free and get off at the last stop. All rentals are there in 1 location.
Yes. They have a short train ride taking you from the airport to the car rental parking.
Very easy as posted. Train ride to the end of the line (8 minutes) where all the car rentals are
Very easy. Same for all major agencies. The train ride takes ca. 10 min.
Very easy.
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