The external paneling was a 7/16" thick T111 and it came already primed. It looks really nice but was a little bit of a beast lining it up so the vertical ribbing matched up.
We added R-11 insulation since we live in Wisconsin and will need to heat the coop. We put wheel on the coop so that we can move it closer to the house in winter when we will need to heat. The pictures don't show it, but we mounted a solar panel on the roof and light fixtures with DC bulbs to extend the daylight in the winter. We added a 24"x24" sliding window for light and ventilation.
We put melamine paneling in the interior and a cheap vinyl floor. We calked the floor/wall seems for easy cleaning. The melamine also acts as a whiteboard so it's really fun to write on. The 6 nesting boxes on the back have an external access door and the end unit with a separate access door is useful for storage of feed, bedding, light bulbs, etc.
We used simple T hinges and hasps for doors and security, and painted it a nice "barn" red.
We were very concerned about the weight of the coop and feared that a traditional asphalt shingle roof would add a couple hundred pounds, rendering the coop almost immovable. So we looked into this really light-weight, corrugated, durable, and pretty cheap ($20 each) asphalt impregnated polymer panel that weighs less than 40 pounds total for 2 sheets together and will last a long time as long as it is installed properly. And although it does not let light through, it does not dry rot like the polycarbonate panels tend to do.
And voila! There she is... La Maison des Oeufs or the House of Eggs.