Delay in refund of paid amount for a 1BHK apartment

Dear Sir´s, I work abroad and had booked a apartment in my wife´s name. According to the Agreement we paid the builder in full (INR 14,16,500) Builder was supposed to complete the building in April 2014. As this did not happen we had asked for compensation with the builder and he agreed to give INR 8000 on monthly basis in the Month of January 2015. But he paid only once and when we started follow up he came up with lot of excuses for which we decided to cancel the bookings and asked for reimbursement of amount paid (even ignoring interest for the amount paid) From then, I am following up this particular builder from the last one year but till date he paid only INR 1,00,000 and gave me a letter saying that he will reimburse the amount partially (2 lacs each from Dec 2015, Jan 2016, Feb 2016 and rest in March 2016) but for also this he failed and till date did not reimbursed my paid amount I am fed up with this firm and their false assurances. What is the best solution to get my money back as early as possible. Please suggest.