Finally done with renting, but the property hunt is stressing me out

Honestly, the EMI vs rent math is finally pushing me to buy in Greater Noida. I'm so fed up of renting, landlord hiked rent again, so I'm finally taking the plunge. Looking at places near Yamuna Expressway, maybe a 2BHK, budget around ₹70-80L. I'm trying to figure out if price negotiation actually works here. Builders like Home Option Propbuild, do they budge much? What's a realistic discount one can expect, like 5% or is it lower? Also, I'm worried about hidden charges at possession. Everyone talks about PLC and OC, but what else sneaks up? And for payment plans, is construction-linked always smarter than a bigger down payment for an investor? Any experiences would be super helpful.