Noida Extension possession - hidden charges ka kya scene hai?

I'm so fed up of renting, landlord ne phir rent badha diya. Finally taking the plunge and buying something in Noida Extension. But I'm hearing horror stories about hidden charges. Like, PLC aur EDC/IDC ke naam pe they loot you at possession? Is it true that some builders suddenly add these costs which weren't mentioned before? My budget is tight, I can't afford any surprises. I'm looking at a project by Gaurs and another by Ace. Anyone faced this with either of them? Should I get a lawyer to review the agreement *before* booking? Also, actual carpet area vs super area mein kitna difference hota hai, realistically? Honestly not sure how to avoid getting ripped off. Any advice? Kitna extra expect karun, matlab? Is it worth buying OC property instead?