Pathetic Treatment By Rental Agency - Please don't deal with this ********* company

I'm renting a property thorugh KW Clockwork Properties. My inlaw's wanted to move in with me. The estate management confirmed that even with my inlaw's living with me I will still be within my limits (in terms of over population). I notified the rental agency (KW Clockwork properties). They told me that they will check with the owner of property. They then came back to me a few days later and told me to pay R500 more (this didn't make sense because my utilities is separate from my rental amount). After much debate, I accepted this. They then told me that they want me to sign another 1 year lease agreement. I disputed this and even got my lawyers involved but they still didn't budge. They bul**** me into paying more and signing a new lease as they knew I had no other choice. Companies like this must be taken to task for their ********* behaviour.