Plumbing nightmare!

Today I got a call from a Temecula home owner that said he had a leak fixed and needed the wet drywall removed. I opened up the wall to find lots of black mold! After suiting up with a respirator, gloves and goggles I removed the moldy drywall just to find that one of the plumbing manifolds looked really bad. At this point I had the water off already to remove a bad angle stop. I knew the plumbing manifold looked questionable as though it were the source of the leak but the homeowner said a plumber had already come earlier that week and "fixed" the toilet which he said was the problem! Lo and behold when I turned the water back on the manifold in the wall was spraying water. This is what caused the mold to spread. I am not sure if the plumber actually found something wrong with the toilet or simple made something up that he could bill for. Home repairs can be tricky and need thorough attention and expertise. Quality and honest work can be hard to come by these days!