OK, I was on level 900 and I had bought a few belted cows. In case you haven’t figured this trick out yet. I take the ‘move’ tool and move one of those ‘ready’ belted cows into my dairy and then it become ‘ready to harvest’. If I have 39 cows in the dairy and add one to harvest it; that’s 40 and I get 3000 coins for each one. That is 120,000 coins for each harvest (harvest with the multi tool). Now you know why I have a billion coins!