I have had some nice chats with some of the Uber/WAV drivers. They are a separate company and subcontractor of Uber. In San Francisco they have two types of vehicles, one that loads from the rear and another minivan that is a side door ramp. I prefer the rear loading vehicle because jockeying the wheelchair in that interior space to fit into the area of the tie downs is difficult. I was told that in San Francisco they can only take you to the airport. They cannot pick you up from the airport, but suggest you ride BART to the Colma station and they can pick you up from there. That didn't make much sense because I could ride BART all the way into town and then have them pick me up from there just as easily. They are not a 24-hour service and operate from 4:00 am to 1:00 am. You cannot reserve one in advance, but every time I book one, a ride is there within 15-18 minutes. I have also had repeat drivers, since their fleet is small. You can get to know them.

I have also used the Lift/WAV.