In one of our MP games on a 4 Corner farm, the wife and I have 3 barns (10 cows, 2 pigs, 12 goats, 12 sheep) and 3 coops (5 blue chickens, 1 void chicken, 6 ducks, 12 rabbits, 12 dinos). With two of us working this, it's not a big deal, but the entire southern half of the farm is pasture for those hungry, hungry hippos.
In our Forest Farm we (will, we're not there yet) have 1 barn (4 cows, 4 goats, 3 sheep, 1 pig) and 2 coops (5 blue chickens, 1 void chicken, 6 ducks, 6 rabbits, 6 dinos). In that one we work it so that only one of us is petting the animals and letting them out, and the other takes care of closing up in the evening.
In my old, original, lost save (my new 4 Corners is a do-over of this one), I originally had 3 barns and 3 coops all by myself. That was too much. I was never done with all those animals and processing or storing their produce until after noon every day. I'll never do that much again without help... and even then, probably not.
In my new 4 Corners solo, the same set up that we're shooting for in the Forest Farm MP (1 barn, 2 coops). In that farm, I only need 1 quadrant of my 4 for them and their pasture. I get a steady supply of stuff that I can use for cooking ingredients and bundles and gifts etc. Anything I don't need, gets sold. That's not how I make money, though. It's spare change and stuff.
I don't play optimized, intensive plays like some folk seem to. These aren't as profitable as spending my whole day of play tending a garden? So? I'm not playing Farmville here. There's more to do than just farming. I like having animals, and I absolutely NEVER do a Joja play, always the Community Center, so you need just about 1 of everything at a minimum.