Someone had a bunch of etiquette experts come up with a list of the ten rudest things you can do in someone else's house. All of them are fairly common things people do, even though they shouldn't.
1. Moving things around. Like rearranging cupboards, or saying, "That chair should really go right over here."
2. Overstaying your welcome. Whether you're there for a party or staying for a full week, be mindful about that.
3. Hiding or ignoring a mess. If you spill wine on the rug, tell them about it. Don't just pretend it didn't happen.
4. Snooping. Don't rifle through their medicine cabinet or go through any drawers. Drawers in bedside tables are especially off limits.
5. Bringing an uninvited plus-one. Again, whether it's a party or a weekend visit, don't assume they agree with "the more the merrier." Always check first. That also applies to pets.
6. Showing up and THEN telling them about dietary restrictions. Plans have already been made at that point. So if you can't eat the food they made because you're gluten-free, that's on you.
7. Feeding their pets from the table. Always ask first, or just don't do it at all.
8. Disrespecting house rules. Like if it's a "shoes off at the door" house, do your best to remember and be respectful about it.
9. Showing up empty-handed. Like going to a party and not bringing a bottle of wine, or a six-pack.
10. Expecting a tour. Some people apparently WANT to do the whole "let me give you a tour" thing. But let the host offer, don't ask for one.