try posting this on the Farm Life forum, there's way more traffic over there.

My chickens used to lay one egg a day. Occasionally they would take a vacation. Some breads are more or less productive.

Based on that, three to six productive egg layers should give you plenty. Start with three birds and ramp up to your needed production.

My coops never smelled to bad but the birds were free roaming all day and my coops were on wheels with screened bottom so I would move it every now and then to distribute the "fertilizer"

As long as the feces don't build up and stay wet it, usually doesn't smell to bad.

As far as clearance from the house. Doesn't matter as long as you don't mind the occasional spooked chicken in the middle of the night. Other wise you may want to keep it a minimum 30 feet from the house and not near your bed room window. Preferably on the side where you can't here it.

If predators are a problem then you may want it near your window.

check out www.the-coop.org . and join free