Commercial tenant right in redevelopment

Dear Experts, I am a commercial shop pagdi tenant in Pune city(Maharashtra) having tenancy rights for unlimited years , I am the only tenant in the building.Other tenants have surrendered their tenancy to the landlord. Few weeks ago a property developer has approached me that he is interested in developing the building (which is more than 60 yearsold) and he has already spoken to the landlord who is willing to sell the property to the developer. The developer has asked me what do i want 1) A fair current market price 2)same area shop in the new developed building My query are If i decide to take a shop in the new developed building ?am i entitled to more extra area or the developer is speaking the truth that i will get only the current area. How will i safeguard myself till the time the old building in taken down and new building construction is complete.Given the certain market conditions Re development is known to stop mid way and can go on for end number of years.I need running income to keep my household and bank emi s going. Please Guide.Thanks