Our house was a self-build by an architect in the 70s (added to an existing older structure) and it is WILD some of the choices that he made. Also, we discovered that at the time, if you built a house yourself, you didn't have to abide by a lot of regulations, which explains a LOT.
On a whole other scale, but they're renovating Manchester Town Hall at the moment and have been for several years, but it's ended up taking a lot longer because they keep finding things like sideways chimneys running under floors because it appears to have been built complete madmen.
We've just had to replace a botched wet room floor and in doing so also discovered why the shower drain couldn't keep up with higher shower settings - the pipe underneath doubled back up like a toilet drain(!?!). Also the entire wall behind the tiles was rotted because the shower bits were internal
We have some friends who have been doing up their house (all a 70s build, allegedly designed and built by an architect but they've sceptical about how professional they were). They took down a wall and found not only a walled up staircase but also a literal sex dungeon.
They sent us photos because they knew no-one would believe them otherwise. It wasn't a very big sex dungeon, but there was absolutely no doubt what it was intended for. Why it had just been walled up (along with the stairs) rather than removed is anyone's guess.
Years ago in LA, I helped a friend clean out his father's Silverlake house after his passing - we found a sliding panel in the back of a walk-in closet that led to a very well-stocked leather daddy sex dungeon
My mom had a box spring with big eye hooks screwed into the corners. I pointed them out and she said, without a moment's pause, "I was trying to hang it from the ceiling." I scoffed at this ruse and she exclaimed "hey it was worth a try!"
