My kitchen sink was out of life. The drain got down to a stand still.
I tried a few tricks, snaking, got it myself to about 3 meters of snake, no luck. Then I called a plumber from another company, big company.. the guy tried hard himself a few hours and it is a respectable guy with lots of experience. No luck either, he didn't even charge me nothing.
As a last resort, before breaking walls, I asked John for a second opinion. He is super well equipped, drain inspection camera and all. He did it. I can't begin to tell you how good it feels, and my walls are intact. Cheers John!
PS> last but not least, John has an engineer diploma from overseas, and it shows in the way he deals with the issues