Noida investment from Dubai: ground truth needed

Sector 4, Noida Extension keeps coming up for investment. I'm based in Dubai and can't visit easily, so I need ground truth. Builders like Chauhan Associates claim fixed prices. But can you really negotiate a decent chunk off a 2BHK/3BHK around ₹80L-₹1.5Cr? Not sure how much wiggle room there is. Also, what about hidden charges at possession? I'm worried about surprises like unexpected PLC or maintenance deposits, especially since I can't do site visits. What should I specifically ask upfront? And for payment plans, is construction-linked smarter than a big down payment for an investor? Trying to maximize leverage and ROI remotely, maybe with a power of attorney. Any experiences?