Renting a house meets a black intermediary. How to solve it?

First of all: judging from the contract you signed, it is an unfair contract. The court will not support his liquidated damages.

What's more, he threatened you by various means, and you have called the police (I wonder if you have collected evidence). If there is, you can sue him directly (even the police). No matter what the police say, the police will not act.