Actually this is not correct. You can bring a car into California at any mileage if it is compliant with the California air quality standards. The 7,500 mile rule applies to used cars coming in that are not California compliant.
The smog fee was found illegal years ago and no longer exists.
If you buy a car elsewhere and bring it in to CA, the sales tax business is complex, and it is big bucks because taxes just went up. Depending where you live it can be 10%. Look at www.dmv.ca.gov for all sorts of information.