Can a builder take maintenance from us without OC & also can he handover Society without OC.

Q: We are Resident of Sanghvi Valley Complex,Kalwa,Thane,Mumbai. Possession of flat is taken in Jan 2010 & we had paid 18 months advance maintenance charges which ended in June'2011. After this .He has given us statement of Expences for the maintainence in which the charges mentioned are too high & he has arranged all receipts- which i am sure is not true. How can we be in position not to pay additional maintainance. Since he is handing over the Society without OC which means OC was not a constraint for Society formation so he should have handed over the Society in 1st 18 months only. He has delayed it just to take the additional maintainence from us. Also can the builder handover the Society to Residents without OC & can he take additional maintainence from us.