I keep mine in a rabbit hutch similar to the one posted but mine has a pull out tray and wire floor. I've had 2 males and 4 females in there at once without too many issues. They were all broodmates (only the 6 of them) so that helps keep the peace. I would let them out into the bird room and they would roam around. The floor has hardwood. The problem is their poop. Some are lighter colorded and will dry crumbly. Those are fine and easy to clean. Some are sticky, tarry, black, and smelly. Those will stain any carpet you may have and are hard to get out. Quail also don't care where they step so you know it will be smeared everywhere.
They love to hide under and behind things. And if you approach them, they hunker down and remain very quiet until you are almost right on top of them and at that point, they "flush" and jump straight up.
They do make good pets, but I'm just warning you about clean up.
If you get them a sand box, I highly recommend a Chinchilla sand box. It's like a little covered house. My quail love them and the sand mostly stays inside the box which is important indoors.
