What did the previous owners do to your home that you actively despise them for?

I'll start with a couple of small things, but the real one is the last one. First thing. They must have somehow knocked a hole in the sitting room wall at some point, but plastered over it and painted over it just before they moved out. (Like after we got the keys and went around the house, the paint was still wet.) But the kicker is that it's a wallpapered wall, so the plaster was just put on top, *over* the wallpaper. It required a lot of work to get that wall into a reasonable state. Second thing. The sitting room carpet and living room carpet smelled of, as we put it, wet dog. But honestly, that's putting it nicely: it smelled of years of built-up dog piss. I don't understand it. We came and looked around the house and didn't notice it. Had they somehow covered up the awful smell? Or did they somehow generate the smell during the few months between when we put our offer in and completion? We hired a proper carpet cleaning machine, but nothing was getting this smell out. Eventually we just ordered new carpets and ripped out the old ones. The underlay under the carpets had large brown stains on, which I don't even want to think about. The carpet and underlay stunk up the garage until we got a waste remover to get rid of them. We had to spend about six weeks with just concrete floors in the two main reception rooms. There are other small things too, but it's time to get to the big one. When we were moving our furniture in, some random black cat snuck in and sat in the conservatory. We got him out of the house but noticed him walking through the back garden occasionally. There was also a big fluffy Siberian cat we often saw wondering around nearby, plus a grey cat we saw occasionally. We just figured this was some kind of neighbourhood cat hotspot. A few weeks later, we were chatting to the next door but one neighbour, who it turned out owned the grey cat, and he said that the other cats had belonged to the previous owners of our house and they'd just abandoned them. So that's why the black one (who we found out is called Pepper) came and sat in our conservatory: it had been his home. There were actually *two* Siberian cats (Alfie and Annie), but they were similar-looking and we'd just never seen them together, so thought it was just one. Our neighbour has semi-adopted Pepper and feeds him. We've put some blankets in the shed and propped the door open so they have a cosy place to go if it's cold or rainy. We put out food for Alfie when we see him, which is probably five or six times a week. Pepper and Smokey (the grey one) often steal the food though. Annie hardly ever visits but we see her occasionally on our neighbour's driveway. Hopefully someone's feeding her. She's still alive, so I guess she must be eating somehow. So yeah, I have no idea how they could have just abandoned three cats. Even if they didn't want them any more, they could have sold them to people who would have looked after them. (Siberian cats can sell for a few hundred pounds!) At the very least, they could have *told us* so we could have started feeding them immediately instead of finding out about it almost two months after completion.