Re: Help overnighting in the San Francisco Bay?
Going out of Redwood City; make sure you are familiar with the chart of South SF Bay. There are lots of places that you can go aground down there at a low tide. On picking up your GF look for a fuel dock or marina with a guest dock and an open gate. With a 23' boat even a boat launch dock will do.
On anchoring out; you will want to have a porta-pottie at minimum. Ask GF if she is comfortable with this, you don't want to have to make a trip in to a marina in the middle of the night. Take plenty of water; estimate 1 gallon/day per person. Make sure you are in a protected area that is deep enough so you don't ground at low tide. Also make sure the boat has a working anchor light.
Personally since it is your friend's boat (more unknowns) I would stay at a guest dock; much easier and less planning needed.