To change the kind of business in the garage which is on pagri

My mother is the current tenant at this garagein chembur, mumbai where she used to run a beauty parlour, due to her aging physically her health does not permit her to run the parlour any more. The landlord does not allow us to change the kind of business at that place saying that the society does not allow, the society is the church as majority of the land in chembur is owned by the church. time and again the landlord has been asking us to give it back to him which we do not wish. As there is an inetrnal property dispute amongst the landlords family he is not accepting any rent from us since 2004 but the other tenants are paying the rent, Now the landlord expired and his wife and daughter in law have taken charge last when we tried to pay the rent she said i have to speak to my lawyer as the property is under dispute. my questions are as follows 1. Can we change the kind of business in the premisses 2. can we get the tenancy rights transfered to any of we children even while my mom is alive 3.we understand that she can evict us if rents are not paid, but she just refuses to take any rent, kindly suggest what can be done 4.what should be the value if i want to sell out the tenency rights back to the landlord or to a third party