Codes are a starting point
A code tells you which system set off the light, not always which part failed. Ray reads the codes and checks the part that set them off. Then he tells you what is wrong and what it takes to fix.
Before a smog check
A car will not pass smog in California with the check engine light on. Come in early so there is time to fix the cause before your smog date.
Ray gives you the price after he has looked at your car, before any work starts. There are no set prices on this site because every car is different.