I think there is a tendency for all of us to think that "previous owners" are a special breed of lunatics; but it often is hard to find reasons why a sane person would do the things you find.

One of the outstanding "features" of our current house is a quarry tile floor in the kitchen, laundry, hall, and an adjacent "rec" room (large enough that they had a 7 foot pool table, with "adequate" room to play). The only problem is that the idiot former owners laid the tile themselves, I'm sure, in concrete rather than grout, and there are mismatches in the level of adjacent tiles of up to a half inch. (Really hard on bare toes when you stumble through in the dark.)

When I decided to replace the "throne" in one bathroom, I found that they had literally poured a 2 inch thick "slab" of concrete over the base of the existing toilet. It took 7 or 8 hours with a 3-lb hammer to get the #@$% thing out, but it did explain why the seat was so low that a healthy young person needed a grab rail to get off it.

Shortly after we moved in I made a survey and found that I would have to keep 17 different kinds of lightbulbs on hand to match intended usage in the existing fixtures when a bulb burned out.

I found one junction box in the attic where our "master do-it-your-cheap-self had stuffed 11 connections (code limit is 4, with the wire size used, in that size box). I've had "adequate" electricians out for a couple of small jobs, and have asked for a bid on re-vamping the electrical systems. They don't exactly refuse to touch it - they just disappear and never come back (and "don't remeber being there" if I call.)

John