New builds in Gurgaon: Real negotiation possible?

Does price negotiation actually work on new properties in Gurgaon? I'm in real estate myself, but buying my own 3BHK in Sector 82A feels totally different. Builders ka "no discount" policy kitna true hai? For a project by say, HUDA Builder, can you really push for 5-7% off the quoted price? Or is it just tiny adjustments on PLC or IFMS charges? Kisi ne achha discount nikala hai recently? And hidden charges ka kya scene hai? Beyond stamp duty, registration, and obvious PLCs, are there other big surprises that pop up closer to possession? Builders often have these sneaky charges. Not sure how much extra to budget for these. Want to avoid any last-minute financial jhatka. Your experiences would be super helpful.