Adani Realty Airport Road: Hidden costs aur negotiation pe thoughts?

Gurugram mein property ki all-in cost samajhna ek alag hi jung hai. Kids have moved out, so we're selling our big house and eyeing a compact 2BHK, maybe Adani Realty ke project mein Airport Road ke paas. My budget is around ₹1.5 Cr. Builder bolta hai no negotiation, but I'm sure kuch toh scope hota hai. Kitna realistically kam karwa sakte hain? Aur ye stamp duty, registration ke alawa PLC, OC, parking charges sab mila ke kitna upar jaata hai total? Yaar, possession ke time koi naye hidden charges toh nahi aate? What's your experience?