The ones that ignore the fairly basic animal regulations eg don't let the lurcher hang around outside without being on a rope, in his run, or supervised by me, and don't let the cat in the house under any circumstances.
They see the sign that reads 'NO CATS STRICTLY BY ORDER', with a picture of my cat, and a red line through it. They say 'You do realise cats can't read, don't you?' and I explain that it's not for the fucking cat to read, it's for visitors. Then they ignore the sign anyway and let the cat eat the entire weekend's supply of food and laugh at me when I have to jump up from my meal in a total rage because he's inhaled half a cake in 10 seconds. (Yes, I feed him - cat food - he's just an arsehole.)
The ones who turn up empty handed and spend the whole weekend demanding booze and tobacco.
The ones who expect me to feed their kids but don't tell me when and what their kids eat, and it turns out that it's always the wrong time and always the wrong food.
The ones who stay longer than agreed, or don't tell me when they plan to leave.
The ones who bring a dog that looks just like mine which then proceeds to savage the neighbour's sheep - which puts my dog at direct risk of being shot.
The ones that come in winter with no jumpers or coats and no idea how to maintain a fire, which essentially means I am on house arrest until they leave otherwise they'll die of exposure.
My ex who comes thinking I'll shower him with sympathy for his weird stalkerish behaviour towards his latest girlfriend, and then gets shitty with me when I point out that his behaviour is crossing several lines and is no longer acceptable on any level in 2020.
I could go on.
But the majority of my guests are wonderful. Some of them make me feel like the guest and keep bringing me tea and cake and food. I'm fine with that!