My favorite QI/Inspector of Everything is Clara, a large mutt born with a deformed front leg and now developing arthritis. (She does not get on furniture.) Her bed seems to please her very much, and is one of the rather inexpensive "bag" styles with stuffing in an inner bag and a zipper on the removable outer bag that can be washed. However, I thought the texture of the outer bag was a bit rough as well as ugly. The overall size is about 3' by 4', and it is about 8" thick. I got it rather inexpensively at one of the "big box" stores. To keep Clara's bed clean, better looking, and a nicer texture I have two twin bed sized flat sheets which I alternate. Every time I change the sheets on my bed, I change the sheet on Clara's bed, too, and just fluff up the bag, spread a clean flat sheet over everything, and tuck the edges under all the way around. And then I toss her used sheet into the washer and dryer, and with a dog with a thick double coat that really helps with hair in the house! Clara not only sleeps on her bed at night (next to mine), but also goes upstairs to her bed for afternoon naps. About her sheets -- Clara sleeps on much nicer sheets than I do! Hers are 100% cotton and with a thread count of about 400, and holding up very, very well. I found them at a store going out of business for $5 each, so I bought two -- very sad that I couldn't find the same sort of bargain for my bed!