As far as casinos, there are supposed to be ways to win at cards, whether it is Black Jack or Poker. But, it is also easy to lose, and casinos don't like it if customers win against the House. Slot machines are designed to just suck the money away to nothing. The slots used to use real coins. But, now it is generally tokens, paper receipts, and credit cards. All designed to just suck down cash.
If the tractors were selling for $5000, and were complete, then it might be worth the risk. At $15K, it is a lot to risk on a project. However, as the video clip shows, perhaps if one could ascertain where the water level reached, it may not be as bad as one might expect. Unfortunately, some of the auction houses like to power wash everything, and thus the level of the water may not be immediately obvious. We have a local tractor recycler that would sell used tires and wheels if they had them. But, a lot of things still aren't cheap.