How much compensation amount can I claim from builder?

I booked flat in thane in May 2011 in a redevelopment project with payment of 10% by cheque (at the base rate of around 5700 per sq ft).I booked at prelaunch stage and the builder kept me telling that the construction will start in 2 to 3 months when he gets commencement certificate.When inquired about the reason for delay in cc and the permissions still pending for the project he refused to give any information about it but verbally promised that if construction work starts in some other building (out of three adjacent building being redeveloped by the same builder) they will change my allocation to that building. Now construction for one of the adjacent building is started whereas my building is still on hold but now builder is refusing to shift my allocation and asking for current market rate for the same. He gave me three options, 1) Shift the flat to adjacent building with current market rate (9000psf) for the same. 2) Wait till the construction work for my building starts. 3) Withdraw my allocation with 12% interest rate on my booking amount. What is the builder legally entitled to pay me ,if i cancel my booking? Can I demand compensation since not I am not capable to buy flat in that locality where rates have reached 9000 psf in last 4 years.