A consumer took a car into a service center for repairs, and paid in advance for repairs. When they returned to pick up the car they were told that it was under new ownership, and that the new owners had no responsibility for their car. When they went to get the car its battery had been removed, and they couldn't tell if any work had been done. The new owners wouldn't even look at the car, let alone find or replace the missing battery. What are the car owner's rights in California?