CSI has ****** us of money and is now asking for more than R10000

CSI robs you for money. We rented through them in Waterfall Ridge. The complex had consistent water and electricity issues. It also had a ****roache infestation. We had contacted CSI to assist us as the complex had fumigated 3 times and we fumigated twice at our own cost. We emailed CSI countless times and they never acknowledged the mails or responded. We decided to leave 5 months before our lease expired because no one can live in such unhygienic conditions and they were not willing to assist us. Before leaving the premises we cleaned the place. They asked us to pay R1000 for cleaning and fumigation which I disputed. They took my whole deposit (R8600) stating that the unit was in a state. They use the whole deposit to redo their unit on our cost. They then charged us the next months rent and an admin fee. Which I agreed to pay on the agreement that I could not pay the full amount I asked to pay over 2 installments in 2 months. They never acknowledged the mail till now. On 24 August I paid half the amount. On 04 September they handed us over asking us to pay R10900 when the initial amount was R8950 and I had already paid R4475 before being handed over. Till now they have not acknowledged that amount or the email and they keep hounding us to pay the 10k their collections team is none the better. I sent an email refusing to pay and they have not communicated or anything. Furthermore they do not communicate or acknowledge anything and expect to ***** our money. I've been nice and professional up until now but I'm extremely frustrated and upset. They just want to keep taking money from us I will not pay the balance nor will I ever rent or buy from them ever again and I will make sure to tell people about this organization they are running where they are robbing people.