Old chawl redevelopment with old tenants

Hello legal advisors, Our family is living in old chawl as a tenant since 1970, located in Kalyan, District- Thane. Chawl room carpet area is 220 sq.ft., Currently my dad is paying Rs. 100/month as a rent to landlord. He is providing rent receipt on the name of my grandfather. Electricity and municipal water supply bill is on the name of my dad. For among all past years, landlord is not treating us well, he always wish to evacuate us. He had also taken Rs. 5000 from my dad for just painting and plastering of inner walls for maintenance. He never permitted us to do maintenance of room and nor did by himself. Now landlord is giving same chawl for redevelopment with builder. Landlord introduced us to the builder. First asking: In meeting with them, firstly we are asking builder to provide room free of cost but he is asking us to pay construction cost for 220 sq.ft. and to bear following list of charges- Society registration, electricity meter, water supply meter connection charges, balcony enclosing charges, borewell charges, transformer charges, development charges and flat registration charges, etc. Second asking: Secondly we are asking builder to provide additional area as we want 1bhk in future consideration but he is asking to pay us market rate for same. So I have few questions as below : 1. Our first asking is valid or not? 2. Is there any rules for developers for providing minimum carpet area room in redeveloped building to old tenants as free of cost basis? 3. What necessary documents we should ask to builder before signing an agreement to avoid cheated agreement and hided charges? 4. If we suppose to agree with developers current offering, then do we have to bear all above of charges or not? If specifically yes then which? Thanks in advance.