Not more than 2 or 3. The prefab coop has more nesting boxes than it needs, too, but there's no fix for that. More run space will make integration easier, but if you are limited, you are limited.
I agree with your earlier post, more space is almost universally better - though some management practices and conditions can allow you to do with less, scarcity tends to create friction, while abundance lubricates relations. Except CornishX - those idiots will happily eat themselves into an early grave!
Would try to locate your additional birds from a local who will sell in smaller quantity, and whose flock and grounds you can inspect for condition of care and signs of disease. Bringing outside poultry in is always a risk, and you don't have the space to effectively quarantine.
/edit and I have 30.8 acres for you duck crazed people. See my flock in my signature. 8 is plenty for my wife and i. Meets our egg needs, most days, and there's one for the table each holiday.
I agree with your earlier post, more space is almost universally better - though some management practices and conditions can allow you to do with less, scarcity tends to create friction, while abundance lubricates relations. Except CornishX - those idiots will happily eat themselves into an early grave!

Would try to locate your additional birds from a local who will sell in smaller quantity, and whose flock and grounds you can inspect for condition of care and signs of disease. Bringing outside poultry in is always a risk, and you don't have the space to effectively quarantine.
/edit and I have 30.8 acres for you duck crazed people. See my flock in my signature. 8 is plenty for my wife and i. Meets our egg needs, most days, and there's one for the table each holiday.