This actually happened to one of the people I know. That person had to go through a lot just to get out of the stranglehold of those people. Literally screwed. They were paying half of market and also not even paying it on time. Unfortunately its difficult to pursue a legal route against these people because of the cost to pay lawyers and also the fact that they do it in such a way that its borderline legal/illegal. The only thing you can do is to save other people who may fall into the same trap.