There is no “certified” inspector in California. Anyone can call themselves one. It’s a scam. If you know anything about construction, inspect it yourself.
https://careertrend.com/how-6130922-building-inspector-certification-california.html
Let me put it this way, if banks would require couriers notaries to be certified and be registered to their own bank to be trusted, do you seriously think "building inspectors" will not be certified and not risked getting sued? The realtors and the sellers not getting sued? Come on now, you know no matter how much you hate California this cannot be real right?