Have you thought about considering other types of schools?
If you decide to look at private schools outside (or even in) California, there are many that have great financial aid, where travel is taken into consideration and 100% of need is promised to be met.
You should take a look at the Claremont McKenna Colleges if you really want to stay in California. I think it'd also be helpful to visit and tour there and some of the public, very large UCs to give you a better feel for what kind of school you like.
I'm from California and also Guatemalan and after visiting a mix of schools I realized that I'd prefer to attend a small liberal arts school. Financial aid is also a factor for my family but as I said, most school have great financial aid.
E-mail me if you have any questions!
It's so awesome to know someone else that's a first-generation college student and Guatemalan.
Good luck with everything!