I stayed at Burlingame Airport Parking, next to the Hilton, this last weekend, at $9 a day plus a 5% tax (some other airport area locations in different cities charge higher taxes). Shuttle is on-request but there were already others waiting for the 5am shuttle when I walked up to the front of the hotel. On return, called the Hilton and the shuttle was there in about 15 minutes. Their lot was less than 25% full and had plenty of spaces. One reason I keep going back here is that I feel my car is reasonably secure - have never seen anyone walk in from the street. When you factor in Uber costs on a lower per-day stay, you might come out pretty close to their rates. I know they used to offer lower weekly rates, and the daily rate could jump as high as $15 in peak times, but I'd input your dates there and see what it prices at.