I used to keep chickens, bantams and ducks years ago. My parents decided to keep 4 hens, my stepfather built a nifty little poultry ark, nest box and roosting section at one end, nice big run at the other, wheels on the back end, handles at the front.
When at certain times that they weren't allowed free run of the garden, once they had gone to roost he would move the whole thing to a new area of the garden. They would scratch out moss and weeds, fertilise and produce lovely eggs!
Keep the house and nest boxes clean, no unpleasant pongs.