I don't have a 'bin'.......I have a compost pile. But I am not bothered by too many wild critters ---a squirrel that thinks he has to bury his walnuts in there but.........
If you are going to leave it open, you can 'surround' it easy with just pallets............and those are often free on our Craigslist....check yours. Set them up on their side and leave one that will work like a 'gate' to go in to turn it.
My own preference is keeping it on the ground. Surrounding it with pallets is a great idea! The reason I like it on the ground is I want all the worms to be able to get in there and do their job. I make sure to layer it and water it (when I remember). Another reason is I had one of those black bin types that sat on the ground but then my cats would play in it and end up knocking it apart or the horse would walk by and pull the top off. I think they both work well it's just a personal preference.
Keep it on the ground so the worms can have access to it.
I'm with frugal fanny on keeping it cheap with salvaged materials.
We used to just do a pile in the garden plot, but now have to keep the dog out of it.
I use fence material, make a cylinder shape & stake it in with the plastic stakes. I had to put a re enforcement of chicken wire around it because the new dog stuck it's nose in to pull bits of stuff out.
We've used a ComposTumbler - https://www.compostumbler.com/StoreFront/home for several years now. The best thing about it - it doesn't become a buffet for wildlife. Nothing more interesting than finding a skunk, opossum, or rats in an open compost pile in your back yard.
It also makes compost really fast - a completed batch every two weeks.
Because we have a dinky, postage-size yard (by design - we mow it with a battery-powered Neuton Mower), we are able to apply a 1/2" layer of compost over our lawn, instead of using other forms of yard care made from chemicals. Grass loves compost, but weeds don't. We have a thick, green, weed-free lawn just by applying compost from the ComposTumbler, and introducing worms into the yard.
Meanwhile, the neighbor, who's yard was put in at the same time ours was, by the same landscape company, using the same grass seed, drags home bags of Scotts several times a year, and still has weeds and not-so-healthy looking grass.
In addition to other's suggestions, your local extension agency may have flyers. Our county solid waste management department sells the beehive looking black compost bins for $15.00. (much cheaper than the store)
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