You cannot beat a crook—even with a team of great lawyers, real estate agents, accountants, private detectives, and other professionals. Even if you successfully litigate, and you get what you think you are owed, the crooks will have taken something else somewhere else along the way, not to mention all the wasted time, effort, and energy that you put into dealing with these people in the first place, and then cleaning up the mess they precipitated.
There is only one solution: Deal with ethical people. You may not make money as fast, but it will last longer, and you will feel better about it.
One tremendous advantage of dealing with ethical people is that they tend to hang around with other ethical people. Your circle of acquaintances spirals into more and more enlightened levels of fairness, kindness, and awareness. Conversely, when you hang with rogues and rascals, your circle of acquaintances tends to spiral into depraved levels of increasingly severe cheating and deception.
Remember, you become the company you keep, so choose your friends and associates very carefully. John Baen is not only one of the most knowledgeable people I know concerning real estate, but he has a heart of gold. That is not to say he is weak— never confuse kindness for weakness.
Be firm about your expectations. Most disagreements come about because of a mismatch of expectations between two parties. Therefore, be aware of your own expectations and, equally important, discuss them with your associates. If you discover a chasm between your way of doing things and that of some associates, turn them into former associates. The world is too full of interesting, kind, knowledgeable, and energetic people to be bothered wasting time with takers, no matter how fancy the cars they drive or the homes they live in.