The size etc will depend on what you want.
If you have space I would build multi coops so you can divide for breeding.
You will want at least....
1 Adult coop
1 Teen coop
and a breeder coop
You might want a rooster pen and/or a meat bird pen
Again if you have space I would build a multi coop.... My favorite one which I can not find the photo of anymore....
a Pole barn type like in this thread
https://www.backyardchickens.com/t/539324/my-new-barn-from-3-pens-to-13
in Washington you would need to close off the ends and only have 1 wall open wire for air. Or they would get to wet/cold in the winter.
Or you can make something like this:
https://www.backyardchickens.com/t/594825/my-new-breeding-pens
Trying to find the one I like
OOOOOOO I like the first one.... Thank You