Tenant not Vacating the shop

Hello, Probelm: I have a property (Shop) of my grand mother, now she is not alive. The property is located in Ponnur and registered under her name. There is no will transfer to her successors. My tenant was staying from 15 years with a minimal rent with a difference of market price 10k. We asked him to vacate the shop since we need a renovation. Issue: He is denying to vacate the shop and asking for three years even after providing the 6 months (not legally provided any notice for 6 months). And we are sure that he will not vacate the shop even after three years also. Blockers: Property is not transferred to the successors and is on the name of my grandmother and she is not alive . My grandmother has 5 children. Now everyone is leaving in different places and the shop is in Ponnur. And we don't have any certificates in hand that we are the legal heirs of that In this case how to proceed to evict him? What we came to know: To sell this property/or to produce court notice we should have succession certificate. If it is the only procedure how to get that? Doubts: Where should we apply it either in the property location or my grandmothers native or anywhere?? If I need to file a case. Can I file a case in the place where I'm leaving like Hyderabad or case should be filed in the property location "Ponnur"? Please advise. If we need to hire you what's the fee