It's my own fault for not investigating closer, but I was under the impression that my San Francisco rental would be picked up at the airport. When I arrived at said airport with my husband, two kids, 4 suitcases, 4 backpacks, and 2 car seats, I was informed by a rude National employee that my rental was to be picked up at the train station, which was at least 30 minutes away, and she could do nothing to help me. I ended up renting a car from Alamo by calling and reserving a car on the spot. I am unlikely to use Kayak again.