I'm going to build a small building on my field, in which to add a little bit of CQB to my mostly open field. I'm not doing nothing fancy, maybe something like two rooms and a short hall. I'm also trying to keep it cheap (I.e. No roof, cheap wood, reclaimed building materials, etc.) I was wondering if anyone could give me some tips or post some pictures so I can get some ideas (or steal yours). Anything will be appreciated!