Query regarding negotiation with builder

The builder's offer of 82% additional carpet area is a good offer, it reflects just how profitable this 6,000 sq. m. plot is with an FSI of 4. You must use this 82% premium to calculate your future entitlement, because that is what you are giving up. Builders usually offer the area bonus on flats. For this calculation, we will assume the 82% applies to your flats, while garages are typically compensated at a flat market rate or a slightly lower bonus. 

When you walk away from a redevelopment project, you shouldn't just accept the raw market rate of your current flat. You must be compensated for the market value of your future promised space, plus hardship allowances. You should demand between Rs 14.00 \text{ Crores} and Rs 14.50 \text{ Crores} from the builder to completely exit the society. Do not settle for anything less than Rs 13.5 Crores as a absolute baseline.

Do not sign the standard permanent alternate accommodation agreement (PAAA). You require a specific Deed of Assignment / Absolute Sale Buyout Agreement explicitly stating that you are relinquishing your shares and rights in the society to the builder/society in exchange for a lump-sum financial settlement. The builder pays the stamp duty on this.

This is purely personal decision depending upon circumstances prevailing market and bargaining /negotiation power of  the parties.

I think builder would have the day being professional in the field.

The posting sggests no legal elements or legal issue.