I’m thinking it depends largely on your personality. Me, being a control freak, would use the rental car and take it to a professional car wash for a full “detailing” before returning it to the rental office.
I have picked up burners at the un-official ride-share spot in Reno, and that worked out fine.
But I read here on ePlaya that in the last couple of years the authorities have been very active with inspecting arriving burners for contraband such a marijuana. And since marijuana is in such widespread use throughout society, I would now be concerned that any given person could be carrying such. And this could lead to your transport suddenly ending near the Gate – a potential case of “so close, yet so far”.
This is a “worst case scenario”, but as a control freak….
(Hopefully the cannabis prohibition will be repealed nationwide soon.)
Dr. Pyro makes several excellent points about scheduling. You may want to study the American expression “cat herding”.
You should also be aware that the USA is a far more automobile-centered society than any European country. San Francisco has better public transit than most areas here, but the automobile is still the primary mode of transportation generally.
You may want to pursue friendships with Bay Area burners here on ePlaya and otherwise. Perhaps in a few months you will know someone well enough to minimize any risk of snafus. But I would hate to see you get stranded on the way there.