what are those Transfer Admission Guarantee program at community colleges?

The community college transfer guarantee is actually quite simple. It states that, if you do not change your major or your intended transfer school after signing, you are guaranteed that 100% of your coursework will be accepted toward your major at the intended university.

A change in major or a change in transfer school will void the agreement – but you can sign a new one which will be good for any new coursework (as well as any prior coursework which is included in the agreement).

If your coursework is not accepted, the community college will pay for you to retake the course.

I think UCI is good option. If your only plan is to go to CC and then attempt to transfer into Berkeley than I would say you would be doing better going to UCI. Of course, finances are a concern. But, CAL and UCLA are the best UC’s, then UCI, UC Davis, UCSB are the next tier and then the rest of the UC’s. So, you are not really improving your chances of getting into Cal unless you absolutely have to go there, or you really hate UCI. You still need to get great grades at CC to transfer and there are a ton of people who are transferring as well. Good luck