I started with this 8 x 12 storage building that was here when I bought the house. It was just your basic building with a storage loft and pegboard nailed to the studs. I needed more height for the water buckets so I tore out the loft and raised the ceiling. I also had to add the window for my AC unit and I filled in the hole that was left from the loft door on the front. After running electric out too the building I insulated and hung drywall. I taped and mudded the drywall but it is FAR from being what one would call "finished" drywall.
Here is what you see when you open the doors.
I built two racks each holding 20 tubs. I usually have 36 -38 tubs breeding at all times. I always leave one tub open on each rack to make cleaning easier. Each tub has 1 male and 2 females. I average between 600-800 rats per month with this setup. I feed all my snakes and wholesale a lot of pinkies and crawlers.
This rack uses the large cement tubs. This is where I grow out the feeders for my snakes and my future breeders. I clean once a week and probably spend a total of about 5 hours a week between cleaning and topping off food and water. In the pics you see Doggy Bag dog food but I am going Friday to pick up Mazuri. I found a supplier locally that can get me Mazuri for the same price I'm paying for the dog food.