Originally Posted by Eastbay1K
I'd differ with your analysis, at least in part. Parking could be up to nearly-$50, but this wouldn't be the maker/breaker. If I could save a full day of rental and parking, and save the time to return the car @ SFO, I'd return the car in the City and take a taxi to the airport the next day, saving a lot of time/stress on the airport trip.
It would help if the original poster indicated where his/her hotel is and when their 24 hour period begins / ends.
If it is a weekend or the hotel is not in downtown, you can dump the car onto the street.