Awesome style, I like it. Cow is a masterpiece. Drawings are very very nice, animations smooth. But the game logic seems a bit strange to me as you are but item and usually sell it with a lower amount of money than you spend, so you either have to stack items or end up without money. Maybe increase the starting amount of money to spend? As every good businessperson, you will lose until you finally start to gain...
When you buy 299 Spartans and place it on top, it "explodes"—however, by description only items above it should be exploded, not the item itself. Kind of lack of SFX for item pickup and sell to the cow. BTW, cow really gives me vibes of Kingseeker Frampt from DS1.
So, very nice. I would buy if you add more scenes, and maybe the ability to craft or to bargain. <3