Booking flat, then the real costs hit

Basaveshwara Nagar mein ek property dekh raha tha, VRL Constructions ka. Yaar, super area vs carpet area ka difference abhi pata chala. Builder ne jo price quote kiya, woh super area pe tha, but actual living space toh kitna kam ho jaata hai! Honestly, I thought it was just a small difference. Plus, registration, stamp duty, interior ke charges alag se. Kitna extra budget rakhna chahiye total cost ke liye? Should I ask about PLC during site visits? It's a proper trap, I tell you.