What is my family’s share of a municipal property under Shari’ah law?

ASSALAM WA ALIKUM WA RAHMATULLAHI WA BARAKATAHU I Asfaq surti son of Marhum Abdul Karim surti request your kind self to show me the right path as to please allah tabarak taala . My grand father Miya Mohamed Abdul karim surti had wife , 3 sons and 3 daughter , 2 sons and 1 daughter got married in his presence , 1 son and 2 daughter got married after he expired . My grand father had one shop in partnership with his mother and brothers and daily expenses of all family was run by that shop. He also has the house in Nagdevi st Mumbai ? 3 where all stayed to gather even after his death. In the year 1971 he bought one house in chawl at Kings circle place near sion for Rs 1,000/- from a trespasser , with out basic amenities ( light , water , toilet , drainage , flooring , security ) this place was military camp , after military left , municipality run schools after some time schools were evacuated and given alternate place , this rooms then were captured by local peoples and sold to my grand mother who after some renovation such as fixing door , window & celing gave on rent , this rent amount was added by my grandmother to meet daily expenses of the family. In the year 1978 due to internal dispute with by mother and My unty ( father sister ) my grand mother sifted us to kings circle room to avoid daily dispute . My parents , me and my sister shifted , My parents paid for the light , drainage , toilet , floring & water . In 1980 my father has applied to CIDCO for the room in Navi Mumbai which was allotted to him. Possession was handed to my father , my parents wanted to shift to the CIDCO allotted room but my grandmother opposed it saying why to shift in Navi Mumbai so far off when you already have the room in Kings Circle near to me and we stayed in Kings circle room in difficult situation . My father sold the house of Navi Mumbai as we were not sifting and if left empty fearing anyone will capture the same. In the year 1981 Municipality served notice to all occupant of that area (97 occupant ) to evacuate this place and to leave immediately claiming us as Trespasser in Municipality premises . In such as situation my parent along with all other occupant formed a society and fought against municipality legally to secure this room as this was our last hope after selling of Navi Mumbai house , All legal cost and hazel were paid & faced by my parents alone . None of my father’s , brothers , mother and sisters gave any kind of support for this vide monetarily nor physically In the year 1987 court ordered us to pay the compensation for trespassing from the year 1968 till 1987 my father paid all the municipality dues for all those years , including those years dues also which was given on rent by my grand mother and the rent was taken by grand mother for daily expenses for full family. Their after the payment of all dues and submission of proper documents to Municipality , they atoned the room in my fathers name as he was the person who fought the case and was present all these years in this room with his family till final survey was done by municipality . We are still compensator ( occupant ) in Municipal record and not Tenant , we don’t pay rent but compensation . My father expired in the year 1998 leaving behind this house , my mother , unmarried sister , self & Rs 90,000/- , My mother staying with me till date and sister got married , self alone spend on her marriage . My father and self spend to renovate this house further adding more amenities and now it is worth fortune. Now in 2008 My father brothers and sisters claims to have the share in this room of kings circle, They want us to sell this house and give them their share. My grand mother is ill , She is not demanding / claiming any shares till date . Request you to kindly give the fatwa in the light of sharihat as what will be the shares of my father’s brothers, mother and sisters , My mother & sister in this municipal property where we our self are still the occupant and not the tenant / owner of the said premises. Thanking you Your Faithfully Asfaq K Surti