Pune property: Gultekdi all-in costs and carpet area confusion?

Visited a couple of projects in Gultekdi last weekend, including Pristine Properties. My wife really wants a bigger 3BHK for the kids, school proximity is key. Builder quoted a price, but I'm trying to figure out the actual all-in cost. Kitna extra lag jaata hai for stamp duty, registration, PLC, and parking? Is it like 15-20% on top of the base price in Pune? Also, this super area vs carpet area thing is confusing. Builders kitna inflate karte hain generally? Not sure if the 1400 sqft super area means a decent 3BHK carpet for a family. Any experiences on how to tackle this and get clear numbers?