Pro tip: I learned to check for a second shutoff valve the hard way
Honestly, I was replacing a bathroom faucet in my 1950s house last month and thought I had it all set. I shut off the main water valve in the basement, like I always do. Started unscrewing the supply lines and got a face full of cold water. Tbh, I panicked for a solid minute, scrambling with a bucket. Turns out, the previous owner had put in a second, separate shutoff valve just for that bathroom sink, hidden behind some drywall in the closet next to it. A plumber friend came over, showed me where it was, and now I check for extra valves on every single job, no matter what. Has anyone else found weird hidden valves in their old house?