LOL, Red Green would be proud of ya, if ya know who Red Green is, Duct Tape, Man's best friend. As for the plumber they charge a flat rate so ya can expect about 40.00 or 50.00 I'd guess just ta get em out ta the house. I just installed one of these and hadta take the cartridge out ta solder it in. Noticed while I had the cartridge out that there is O rings in there. Your problem could be that the O rings are worn so the water pressure is pushing the cartridge out and allowing the water ta flow. You can pull the cartridge on my Moen just by taking the knob off then pulling the stainless cylinder off which exposes a brass clip. Pull the clip and the cartridge pulls right out. New O rings are a snap ta change and your local plumbing store should have em

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