First thing you have to check is the license on WWW.CSLB.com to make sure:

1. The license is Active.

2. The name, phone number and address of the license is the same as the advertising. For example if on the CSLB's website the name of the company is different from the one they calmed on their advertising that means they are not licensed.

3. Check if there was a complaint against their license.

4. Ask for proof of liability Insurance and call the Insurance Company to verify the policy.

5. Ask for few references for similar jobs.

6. By law they must have their license number on the website, business card, invoice and all other advertising otherwise there is something wrong.

7. If the company is a corporation or LLC you can check the status of that company on http://kepler.sos.ca.gov/ under business surch and make sure that business is active and in good standing status.