Yeah, there has been some... interesting... wiring in the house. Built in 1913, it had knob and tube run throughout, but upgraded around '60. So, I have found in-wall splices mixing Romex and K&T, along with some further oddities from the '90s. Any old house has weirdness to it, but the neighborhood here wasn't always as nice and many of the houses have a track record of half-assed homeowner "fixes." On the plus side, my neighbor is an engineer, so the last owner would call him to help fix anything that came up when he owned it. So the most recent stuff is good, but I am always finding something new, and any fix takes three times as long and costs twice as much.
Also, nothing off the shelf works. I had to install a new wall fan in the upstairs bathroom, and ended up having to modify a standard unit by removing mounting tabs, chassis punching for new electrical, etc. The old unit was a ceiling fan that was too thick for the walls, so they built a box around it. Which still didn't fit.