@Brad Gibson This is a fascinating and enlightening thread. Thanks so much for sharing your experience. Something very similar happened to me about 2 months ago.
The way I see, the range of possible responses fall into 3 general categories:
1) You were wronged and the bad actors must be punished for their actions. - I see this as mostly an emotional reaction. Sure, you may teach a few individuals a "lesson", but you're unlikely to ever run across them again in the future, so your business doesn't get any direct benefit from it. If there are low-cost (both time and money) ways of achieving this, such as filing a complaints, it may be worth it to put on your resume so you can tell awesome stories like @Jay Hinrichs', but other than that, it's just spite. My suggestion for this type of thing: very clearly define your personal code of conduct, but don't expect others to match your integrity. Setting your expectations low for other actors in RE will probably save you a lot of frustration. Like you said, it can be a slimy business.
2) The law is the law, and must be enforced. - again, this is mostly an emotional reaction, but with slightly more merit. Your business may get some benefit depending on the cost/benefit of whatever legal actions you take, but it may not. However, being a smaller player, you're not going to fix the entire industry with your actions, nor should you be trying to.
3) Fix the deal or walk. - As REI investors, this is what we do. We fix problems in order to make money. Do the numbers, do a cost/benefit analysis of whatever actions you can take to make the numbers work better (within your own ethical bounds), and optimize for potential outcomes. If the cost/benefit doesn't come out in your favor, move on. There are plenty of fish in the sea.
In case my bias wasn't completely clear, #3 is the way to go. :) It sound like that's the route you took, so I applaud you for that.
James