Every hotel chain forum has lots of threads that describe how a hotel in that chain messed up someone's stay, what compensation they offered, what negotiations took place, and what finally happened. Go through those posts in the forum of the chain you have in mind. They will at least give you a general idea of whether or not you were treated consistently with some other people.

Keep in mind, though, that bringing in lawyers is a last resort. Unless you have a cousin who is a lawyer and will take on your case as a favor, it is very unlikely to pay off. Any major hotel chain has a bazillion lawyers on its staff, is going to pay them even if they're not busy, and might as well put them on your case. They have seen hundreds of cases just like it; if your lawyer is lucky, he or she will have seen two. By the time you subtract legal costs from the value of any settlement, you're likely to end up worse off than you are now unless you have an ironclad, open-and-shut case for a substantial amount of tangible damages that you can quantify, in which case they'll settle when they get your lawyer's letter rather than fight in court. In most cases, the wiser course of action is to take their compensation offer.

Another option, should you care to pursue it, is to contact one of the travel consumer assistance columns in major publications. Hotel chains tend to follow Mark Twain's advice with those people: "Never pick a fight with someone who buys ink by the barrel." If your case is interesting enough to make their cut - they pursue, and publish, only a fraction of the complaints people send them - that can be the most profitable path of all.

If you decide to post about your experience on TripAdvisor or a similar site, be sure you have all your facts lined up. Those sites sometimes remove negative reviews when the hotel/restaurant/etc. disagrees with what they said at a factual level. Also, while that may bring you some satisfaction, it probably won't get you any compensation. (My wife and I recently decided against going to a specific restaurant in Ogunquit, Maine, because of a TripAdvisor review that documented how poorly they handled a specific situation. That didn't do anything tangible for the person who wrote the review, though.)