I have 6' high 2" x 4" welded wire fencing and I think a 2" square poultry netting over the top. Part of this yard is on the north side of a cinder block building the other part of their yard is on the west side. On the north side they can go under a 4' x 8' coop I built for them. On the west side they can walk up a ramp to the 4' x 8' coop or they can go under a tarp I have thrown over part of the top of their yard to keep their food dry during rains. Or also on the west side they can go under a stand of cow itch. Cow itch is like tall broad leaf weeds that will make a cow itch (and me) when you brush up against it. They prefer laying under the cow itch during the day as it provides the with excellent natural shade.
I also have log roosts about 3' off the grown that I've spanned two corners of the yard with. They like to get up on them at night.
Think of a big backwards " L " that's the way their yard is shaped. I know I used 100' of fencing for the perimeter of their yard so it's plenty big enough for lots of turkeys
I'll snap a picture or two tomorrow for you - because sometimes a picture is worth a 1000 words. <--- expecially when it comes to me trying to explain something like this...