Aaaaa Smog Center-Test Only-Free Retest at 2134 Market Street, Concord, California.

I keep going between a 4 and a 5 for this smog check location.

On one hand, the service was great, got in and out within 15 minutes during my lunch, and it's a smog check only so I didn't get sold things I don't need. On the other hand, with a coupon I still paid 40 something dollars for everything, which by my standards, is quite steep for a smog check.
i highly recommend the place. Hope tall guy with the long hair helps you out because he let my car pass with flying scores lolz.
But at the end of the day, I will have to agree with people that getting good services is worth paying for.
Will definitely recommend to my buddies.