Upgrade Parts Cheat

Here's a list of all the country living cheats:
https://www.carls-sims-4-guide.com/expansionpacks/cottageliving/cheats.php

Not a cheat, exactly, but if you complete the Nerd Brain aspiration, you can fully upgrade the coop instantly using your aspiration reward trait.
And to exactly cheat, you can give yourself that trait using cheat codes.

Unfortunately, I found that even with a Sim who had nearly maxed his handiness skill, any farming upgrade parts I cheated my sim (by shift clicking on an animal sheed or coop) did not register in my sim's inventory when I tried to do a particular upgrade. You know how certain upgrades require 6 parts or whatever. The game would only count the upgrade parts my sim had obtained through the errands with Kim the grocery lady. (I found this out because I had five parts and tried to cheat myself one more, but the game refused to count it). I also found it wouldn't count farming upgrade parts that I had another sim gift him with for some reason. It's all very odd and probably has something to do with the errand system.

LittleMsSam has a mod that offers the livestock upgrade parts for sale: single parts or in multiple discount packages.

LittleMsSam Random Small Mods Buy More Upgrade Parts is the first mod listed on that page.

I personally don't want to cheat, but the upgrade parts are way too rare it seems.