Dwarka 3BHK hunt: My negotiation dilemma

Been looking for a 3BHK in Delhi for months now, trying to upgrade from my current 2BHK in Vasant Kunj. Sonu Lamba ke projects bhi dekhe hain, especially near Sector 19 Dwarka. My budget is around ₹3Cr. But yaar, pricing aur negotiation mein bahut confusion hai. Kya lagta hai, New Delhi mein builders ke saath kitna realistically negotiate kar sakte hain? I'm talking about actual price reduction, not just some freebies. Aur ye hidden charges ka kya scene hai? Possession ke time kya extra costs aate hain jo initially nahi batate? Suna hai ki construction-linked payment plans mein bhi bahut loopholes hote hain. Should I push for a lump sum discount or try to spread out payments? Investor perspective se, which approach is smarter for maximizing value? Already home loan chal raha hai, so every rupee counts. What's your experience?