Trouble in seeking advance refund- Rental queries

Q: Dear Sir

We stayed in an apt in Goregaon on rent (Bangur Ngr, Mumbai) from Jan 2013- Aug 2014. While leaving the apt the owner refused to pay us the
20 k from the 1 lakh deposit. He cited the following deductions.Rs 10,200 for car parking, Rs 3500/- for AC repairing, 2665/- rent towards additional days.
and the rest towards gas and electricity bill.

While we agree for expenses towards rental, light, the contract doesnt mention the expenses to be paid for parking. The AC which was repaired while we moved in broke down
within a month as it was already an old one. Also the breakdown is due to internal technical issues and not external.

We have not used the pipeline gas connnection and hence we are not eligible for the payment. The contract also has not mentioned
anything on the same.

The owner have been totally harrowing us since the time we have shifted to his house as that house was full of leakage and he never bothered
to rectify the issue. In addition he is now refusing to return our money which we believe is our due.
Request your help.