Gurgaon mein all-in cost ka kya scene hai?

Institutional Area — just got possession for my 2BHK from Ambey Rani Developers in March. Pre-launch price aur final all-in cost mein zameen-aasman ka farak nikla. Stamp duty, PLC, parking sab add hokar ₹1.2 Cr touch kar gaya, jo initially ₹90L bol rahe the. Kya yeh difference normal hai? How much negotiation is possible on these extra charges?