I had booked a flat with a builder in Mumbai in 2007 & got allotment letter in 2008 stating the rate per sq ft ,area of flat & receipt for money paid to him for the Project.Now it is understood that he has got clearances to commence construction.He has now sent a letter cancelling the allotment as he can then sell the flat at a much higher rate.What is the best & fast course of action to retain the allotment,by going to Consumer Court or civil court.Also is there a time limit by which we should reply to such letters.My intention is to try out persuasive means as Courts will take tremendous time & I am already 64 years old.