Mine may not be the prettiest coop on the planet but we made the ancient coop that was already on the property work for us.
The outside is 20 by 10 feet (ish) going to have to move it though to get the grass back. With 2 ducks it's impossible to keep that pool clean longer than a week (have tried the Braggs vinegar and shading it with the table = no luck)
The inside area that is more open is approx 20 by 12 feet (ish). Goal is to get more sand in there for the floor. You can see the 5 gal buckets I'm going to use for nesting boxes. And I keep the leftover feed and scratch grains in a Tupperware container. The hanging waterers are probably the greatest thing I ever purchased. The feeder was there from the start.
This part of the coop is still under construction the plywood will eventually be a hinged door with just the bottom cut out for the chickens to go through. The inside is all solid walls and more sand floor. Planning to put the nesting buckets in there and the roost that still needs built. Goal is that that side will stay warmer in winter with less breeze going through. That side is another 16 by 12 feet. I'd say for 10 chickens and 2 ducks they can't complain. Would love to let them free roam our 8 acres but I've got 3 dogs that would have a hay day with that.