Property Purchased in 1984 but still no possesion

in 1980, My Father had Purchased land or rather paid earnest money XX and made agreement for the purchase of property for XXXXX amount. Currently the property had 3 heirs and property was undivided. We had made agreement with one of the Hier say ABC based on his divided part he would get.The agreement do not have any timeframe- it is mentioned that when the dividation between the hiers is complete the ABC heir to execute the sale deed done with us. The dividation between the hiers took place in 1983 with all the hiers having equal parts. ex: total property of 25000 sq ft was divided in 8333 sq ft each. We had agreement to purchase 5000 sq ft.out of his part. for which we had already paid him 50% amount. After dividation, now the ABC has refused to execute the sale deed nor he was ready to pay the money we had given him. My father filed a case against him in the distcrict for execution of the deed as agreed upon. The case is still on going. In 2008 the ABC sold his property to builder for which we sent an notice to builder and ABC before the deal was completed within them but then also these guys completed the deal even the property was in to litigation. Now the builder has constructed the complex in the frontage side and we are still in the court to get the justice. In recent event in sept2014, the court has directed us to pay the duty fees (stamp duty) for the property which comes out to be very huge amount. Even if we plan to pay the duty what are our chances to get land as executed in agreement.