I got called to do a camera job at a house where the HO (house flipper) had done his own plumbing (inspected and passed lol) Upstairs bathroom bath,lav, water closet. No Vents used AAV's set in tile walls no access. Water pouring out of downstairs ceilings. He wanted me there because he knew he had set the AAV's below or near the flood rim and thought a slight back up was causing them to leak. I knew I was in trouble when I ran my micro drain in the middle fixture (lav) and it came up the toilet! Then in the toilet (on left) and it came out the lav. OK I am used to this on old galvanized crosses, usually just place a cable in one and camera in another meet at cross, then do what ever is needed to get down stream. Problem do this and find another cross! He can't really remember how he did the job, I know it is just a soft stoppage and continue trying different snakes, double drop heads,bent cables,cameras,fishtape everything I have, the best I can do is get the micro drain(glad I bought it very flexible) to the 2nd cross to view the stoppage which is in the 3" stack on the vertical. I finally said this is an un servicable drain you built and we need to cut the pipe and open the wall below or drop to the basement and cut there, he decides the basement because it is drywall and not laff and plaster like the first floor. Cut the 3" in the basement, used the k-60 with 7/8" going up and it even bogged down! Stayed with it and got at least 4-6 white mice! Of course the renter came in and said it wasn't her When is ridgid going to make me a Micro Drain with optional front laser?