Capt it would make a great shooting house
since its insulated even double paned windows and a steel entry door. Maybe put a couple high back office chairs in there with a heater heck maybe even a twin sized bed in case your elderly father wants to use it and needs to lay down often times.
Bob yea at 10x12 its not real big but sure quite large for a shooting house I originally built this for two purposes to allow my father to be comfortable while hunting as he has many medical problems and also while my wife doesn't hunt she does love to watch wildlife and read a book so in the off season she can open the windows sit in the comfy chairs read a good book and watch for animals coming to the food plot this sits next to. Oh I'll get ya some pics of the old out house complete with the moon in the door.