I use milk crates. I first used them upright with the opening on top, but the chickens would roost on the edges at night and make them yucky, so I changed to the opening on the front. I secured a board about 5"x 13" to the front bottom lip with wire ties (drilled a couple of holes), and that helps keep the straw and wood shavings inside. I stacked two of them together to make better use of space, wired tied them together, and wire tied a board on top to block the holes on top in case a chicken sits on top at night. I also put a piece of cardboard in the bottom of each crate to block the bottom holes. The chickens like them very well, and my eggs are 200% cleaner now. I don't have a ladder to the top one, but they have no trouble hopping up there. I did set a couple of bricks on top to help with stability.