My first "Public" post. Hello, everyone, and thanks for the great info up here! I guess it's a sign for me that the first post is about storage and manure, not chickens (sigh).
There is a guy that has a company called Red Worm Composting in the Temecula area that uses those as worm bins. He collects horse stall clean-out horse manure from customers, puts it in a pile and composts it for a few months. When it has aged a little, he sells some by the ton as amendment, and some of it he puts in the bins, which he has lined in big rows on his back lot.
A ways back he put a healthy starter chunk of composting worms in each bin, and kept feeding them the manure. I think worms multiply at an average rate of about double their weight every six months, so now they have filled the bins and are turning the manure into castings (worm droppings) at a good clip. He put an irrigation drip line that runs to each bin to water it lightly once a week. The containers are elevated and perforated, so they keep a great moisture level and drainage rate for worms.
He sells the castings by the yard, and they are great for plants and worth the cost if you can afford them, but not cheap. I think it's a pretty good idea for taking a waste product and making money from it.
If you have manure or shavings/chicken bedding that was aged a little, you could try it with that, as a way to save costs for fertilizer. I don't know where the break-even point was on the bin purchase vs. the selling point for him, so I don't know if they would be worth it for a non-commercial operation, but if you do purchase fertilizer, it might work for you.
There's my two cents. Probably worth that.
Thanks again to all.