A job in an old Boston brownstone taught me to check every box twice
Found a live knob and tube behind a wall we were opening up, the homeowner swore it was all updated. What's your rule for dealing with hidden surprises like that?
That line about checking every box twice is dead on. I've learned the hard way that "updated" can mean a lot of different things to a homeowner. My rule now is to assume nothing is as described until I see it with my own eyes and test it myself. If a wall is coming down, I'm scanning and poking around before the first swing of the hammer. It adds time upfront but saves huge headaches later when you find the real story behind the plaster.