If you think about it, a lot of tack room space is wasted barn space because the middle is open walking area. You can make a tack locker as big as you want. I figure I can fit three harnesses very comfortely or a saddle if I ever got a full sized horse on one side and my grooming tote, farrier tools on the other, bridles hanging in the doors as well as halters. I am going to put a whip holder on the side and some rods for their fly sheets. Spray bottles and stuff in the doors. Treats and supplements in the bottom. Should hold all my stuff. And like you mentioned, it will cause me to only keep those things I need and I can lock it.