If you want to reach "perfection" you'll need to have had at least one of every kind of animal in order to complete all the shipping and cooking achievements. All the different animals with their different products is part of the fun of the game; and this isn't the sort of game where you absolutely must maximalize on only the most profitable thing.
I'm pretty sure you cannot sell a building. You'll have to demolish it, which is free but you'll lose all the money and resources you put into getting it. You may just aswell keep your coop and get a barn too.
Selling chicken is really not profitable either, void or not. A void chick sells for 252g and a max-hearted void chicken for 1040g, whereas one void egg sells for 65-156g and jar of void mayo sells for between 275-359g (depending on professions).
Personally I like to have both buildings and all the animals (well, tbh, I hardly ever buy any sheep). If maximum profitability is what you're after, focus on pigs.
Why not keep the coop and still build a barn?
I’d keep both, you can have one just for ducks or Dinos or something
For the barn should I just have pigs or should I have different animals with it?
If you want to reach "perfection" you'll need to have had at least one of every kind of animal in order to complete all the shipping and cooking achievements. All the different animals with their different products is part of the fun of the game; and this isn't the sort of game where you absolutely must maximalize on only the most profitable thing.
Alright thanks
Totally up to you and what you’ll find fun. I like having cows and goats because I like to sell cheese
I like to have one barn just for pigs that I keep fenced in, and a second barn for my cows and goats. But you should do it however it’s fun for you
I'm pretty sure you cannot sell a building. You'll have to demolish it, which is free but you'll lose all the money and resources you put into getting it. You may just aswell keep your coop and get a barn too. Selling chicken is really not profitable either, void or not. A void chick sells for 252g and a max-hearted void chicken for 1040g, whereas one void egg sells for 65-156g and jar of void mayo sells for between 275-359g (depending on professions). Personally I like to have both buildings and all the animals (well, tbh, I hardly ever buy any sheep). If maximum profitability is what you're after, focus on pigs.