We just moved about 6 months ago, in this house it has a large basement 1/2 unfinished. My wife said you can have 15x13 ish to do what I want with for my "gun room". So I framed it in and put drywall over plywood to keep out others. Have a 3' steel door and just set up the inside like I wanted. Have a small sterio, budget ran out for surround sound and don't forget ventilation for heat air. Mine had two walls that are foundation and two walls that are framed. One small closet and I am off and running.
This is probably not a huge help to you but it worked for me.
__________________
|