Do your homework and ask lots of questions while interviewing potential Home Inspector firms. As I'm sure you know, the home inspection industry in CA is largely unregulated and home inspectors here are not licensed. Anyone in CA can claim they are a home inspector.
Check web directories and ask agents in your area. Your agent should NOT directly recommend one particular inspector, although they may have a list of HI's they have worked with in the past. They should give you the choice.
At a minimum, your HI should:
Carry General Liability and Errors & Omissions insurance.
Provide you with a computer generated report and photos.
Provide you with a pre-inspection agreement.
Provide a copy of their written Standards of Practice which should align with those of ASHI or CREIA.