My first property budget shocker in Madhapur

Is it normal for the final property cost to jump almost 15-20% *above* the quoted price in Madhapur? I'm looking at Salarpuria Sattva and after stamp duty, registration, GST, maintenance, and interiors, my 2BHK budget of ₹78L feels short. Kya yeh sab common hai? What else did you guys budget for that I might be missing?