Betrayal by father

My Grandfather had willed one of the house, equally, in South Delhi to two of his son, one being my father. My father was in possession of the house since we stayed with my GF. After 12 years of my GF's demise, my uncle wanted to claim his share of the property and he moved in to live and probate/mutate the property. The property went into dispute since my uncle wanted to  build or come to some conclusion about the shared space and my father was not prepared.  Eventually my uncle wanted to sell his portion and my father went ahead and put a stay on the proceedings. My uncle did sell the property to a land mafia since my father would not agree on any mediation or compromise. 

After eight years of fighting the court cases with him and loosing my mother, in the process, I made him come to the negotiation table with the land mafia guy to bring in a builder to build the house. The builder bought the land mafia guy and is in the process of finishing the building. For this project to go on as as a family we needed to come up with the money as my father wanted 2 floors and a basement. It was a substantial amount. It went in as a construction cost for the building. Builder got two floors and we got two floors and a basement.

My younger sister and I bailed my father out and asked him if we will get the floors or shared living spaces. We are two sisters and one brother. We all are married and have children.

 

Seven of us verbally agreed to a plan to share the space. My father agreed too. We were two months to completions , my father and my brother have changed their stance. They no longer want to abide with the family agreement. They say, we will give your money back with interest and I will will the property. He is 85 years of age. As a elder daughter I have cleared his messes and bad decisions all my life. 

 

This is a shock to us both the sisters and there is no reasoning working with him. The property went double in value and he and my brother along with my sis in law see and hear no reasoning.