we had entered a sale agreement with my father-in-law of house and paid an advance - period of the agreement was 2 years that expired on May 2011. My father-in law did hypothecate the document and released the document on July 2011 so we were not able to buy the property as per agrement date. now when we are ready my fatherin law is not willing to sell the property demands more money. what can we do now. agreement is not a registered agreement