I get terrible allergic rhynitis at times so I am really particular about dust. Lived in Burkhardt house last year. Attached bathroom was OK but got steamed up loads after a hot shower. And the room window had to be left open to let out the steam if bathroom door was left open otherwise the fire alarm would go off (I had a flatmate who let the alarm go off twice in one night because of that). The rooms are pretty big. I'd say one of the biggest compared to all other halls. Closet is very small. Storage space above closet's OK. You can chuck some stuff under the bed, too. Dust wasn't an issue for me. As it got closer to the Summer though, rooms got to be quite warm so leaving the window open most of the time helped. The cleaners come in on a daily basis and I think vacuum the place up twice a week. Excluding your own room, of course - that you have to keep clean yourself.
As for shared toilets of flats.. I think it depends on where you live but from most of what I saw it was like this: One big apartment that consits of several rooms (7 to 9 was it?). Could be on one level or split level. So you have a door to that big apartment. Once you enter, you've got all the rooms and one of the rooms would be the living area/kitchen. And a seperate room (meaning door) to toilets/showers/bath. Hope that helps/makes sense