Delhi property negotiation is mostly a facade

Vasant Kunj Enclave keeps coming up every time I shortlist something. Fed up of renting, finally taking the plunge. Looking at DPH Buildwell projects there. Does negotiation even work in Delhi, especially for new properties? Builders seem so rigid. I'm wondering how much you can actually knock off the sticker price, if at all. Also, is pre-launch pricing really a discount, or just marketing? And for an investor, is a construction-linked plan smarter than a larger down payment? Trying to maximize ROI, you know. Has anyone actually gotten a significant reduction?