I would go with the Cuesta->UC/SLO option… Except, if you planjed on going to Boulder, you probably don’t have housing and I don’t know how easy it’ll be to find a room in a house with students that Kate in the year, and for what cost. Since you live in California can you go and see if you can find an affordable apt (never pick an apt sight unseen)? Of nothing’s available then your question is moot.
Roughly speaking both Davis and Boulder are superb programs.