Earlier quoted context omitted.
So what you are, in effect, saying, is that these poor people would be better off if the owner of the trailer park would kick them all out? Then they would not be "exploited". I am inclined to believe you are a troll, because the distinction between an aggression of violence and a voluntary free exchange on the market is quite easy to make, which in your argument you fail to do.
If every time you took an ambulance you were forced to sign over 80% of your wealth or be left to die in the streets in a 'voluntary exchange', that would be exploitation. The difference between that and slumlords is simply a matter of degree. Desperation is the route to profit in both cases. Truly voluntary exchanges without gaping chasms of systemic inequality do not provide opportunities for sustained profit.
What is wrong with this scenario? If there were no ambulance service I automatically choose "Die" (which is, apart from matters of inheritance, always the wrong choice), but if there is the ambulance service I can buy my life for the relatively meagre price of 80% of my wealth, then having neither children nor wife I would take that deal ten times out of ten.