Ok here are some pics of the one i built, this cost me nothing except for the paint and camo fabric . Im in construction so i had all the wood just laying around the garage.
It started out as a kids play ground fort that my kids didnt play on anymore.
Then I just framed it up high enough to stand in
Slapped some plywood on it and cut out windows and a door and the pieces i cut out for windows and door i just put some hinges on them so i could close it up for after season. I did frame around the dor and windows for more suport but not shown in the pics. also added a bench seat
Then I just added some sheet metal for a roof and painted the inside black and the out side a olive green
and the final touch was some camo type netting and made curtans out of it that can slide open,dont have a good pic of the camo netting but you can kinda see it in this pic
The only thing i would do diff if i make another is to make it deeper to shot a bow out of easier and also add some sort of slideing glass windows, in the winter it can get pretty cold in there if the wind is blowing.