Probably depends on your property and infrastructure.

So far, Rabbits have been the easiest for me on 1/2 acre. I have breeders in cages, grow-outs in tractors.

Right now I sell a few kits for covering my feed costs, so feeding them is free.

I add Biochar to the bins under the rabbits to super charge the Biochar and make even better fertilizer. That fertilizer will be going to feed fodder trees from Nick Ferguson. Those fodder trees will be going to feed the rabbits and limit my reliance on outside sources. Eventually it'll be a closed system.