Cheating by builder for maintenance

Respected sir, I bought flat in kolhapur.but while doing saledead I hv been asked by builder 12000 against maintenance for April 2014 to March 2015..we did saledead in month of August 2014.. Completion certificate is from July 2014. And I hv position later which dates Nov 2014... Now main thing is he allowed us to stay from Jan 2014.. Now while we ask for details of maintenance.. He send us rough details..while we cross check we found gape of around 1,50,000 inr.. Then we meet him in office and he send another bill which shows gap of 92000 inr and he charged 22000 service charges in bill...I don't hav any written proof for that but I have recorded phone calls as it is my default setting in phone...n when we went last time he told that he will not give anything and insulted.... I got video evidence of that...can I complain in consumer Forum?...and do that video and audio proof can provide as evidence of paid 12000 inr.?.. And from which date builder is legally entitle to collect maintenance from flat owner?