We made a coop that first was for 4 chickens, but we doubled it to make it for 8. The run is only 8x4ft now so we are going to make a portable pen that we can add to this one that is larger. We spent about $200 for the supplies, but if you did not roof it with shingles you could cut that price way down. It was over $50 for the roofing. WE got the plans off this video, but we made it taller and wider. and moved the nest boxes to the side and made one large door for the back:
The coop is two stories. The top coop is 4ftx 4ft it has two external nest boxes and a floor and two roosts. The one under it is also 4x4 and has a roost and 4 nest boxes. (one with a divider on each side) They both open into the run. Both have removeable floors so that they can be easily cleaned.
We put four wheels on the bottom and it can be rolled by one person, if you were turning etc, you would need two. We took the design off youtube, but did not roof it all the way. We put a tarp across the run (lighter), I think we would do something different for the roof if we were to do it again. Shingles are heavy, but it is quite water proof!
Here was the coop before we enclosed the bottom to make another coop., just so you could see the length. It now has the four wheels and hard wire along the bottom so my lab wont break in to eat the chicken scraps!
Here is the bottom coop (the nest box anyway) and you can see the wheels, I also used wire cubes to reinforce it. I had some. I use cubes and zip ties to make grow out cages and rabbit cages. You can google cube cage and see all kinds of things people do with them. They are handy.
edited to add a full veiw: