Cleanliness; as others have pointed out, in my younger days, not a huge deal, but now, sorry, I can't deal with filth.
Making some effort to accommodate me. I'm not saying my host has to go out and spend a fortune, but at least provide the basics, and if you don't have them, or want them, please let me know so I can bring them. as in milk or cream for my coffee. I've actually brought an entire small coffee maker and fixings to one friend's as she doesn't drink it. And she was fine with that.
don't make me hunt down towels, extra blanket, etc. Ask me what I might want or need, and i'm ok with you telling me where stuff is, but don't leave me hanging.
Other than that, I'm fine. for a night or two, I'm fine on the floor, couch, futon, air mattress, etc. I'm really not fussy.
I prefer to stay wiht one cousin and his wife since they "get it" His sister, not so much. she's more of an oblivious host; and her SIL is not, which is why I'd rather stay wiht them.