Budget finalised, loan pre-approved — now stuck on which sector

I'm eyeing a 3BHK in Sector 81, around ₹1.1 Cr, from Spes Construction. From my experience, negotiation is crucial for investor ROI. Builders often quote high, but kitna realistically knock off kar sakte hain in Greater Noida? 5-7%? I've seen builders become flexible towards quarter ends. Also, for better deal value, is CLPs vs upfront down payment smarter? Sometimes builders give better pricing for higher down payments, but that locks up capital. What about hidden charges jo possession pe dikhte hain? PLC, OC, maintenance ke alawa, what else should I factor in for a project near FNG Expressway? Community ka kya opinion hai, especially on current negotiation tactics in Greater Noida? Any specific insights on Spes Construction's flexibility ya Sector 81 ke market dynamics? Need to make a calculated decision.