the answer is "a lot". A few weeks back I asked how bad the smell would be if I kept quail in the house. Well, my 8 quail are nearly 4 weeks old, and the smell is pretty bad. I have them in the house in a large carboard box as a brooder, and am hoping to get them out to the garage in another 2-3 days, then eventually outside. I just turned off the lamp a few days ago. They're on woodchips, and I dump new woodchips in with a little bit of baking soda, every few days, and they still smell. I have a very sensitive nose, I should add. They are also dusty now, as someone else mentioned. I didn't understand the dust thing until they started stretching and flapping their wings and bopping up toward the top (I have netting over the top), and they get dust and small feathers everywhere. So, moral of the story - if you're going to keep them in the house and you have a sensitive nose, plan on either kicking them out of house when they're old enough or change/clean the cage at least every other day.