Thinking about my first 2BHK in Phi IV, need advice

Is it really smarter to go for construction-linked payment plans in Noida Extension, especially with builders like E3 Infratech in Phi IV? I'm looking at a 2BHK around ₹85L. Should I push for a down payment discount instead? Also, is going direct to the builder better than a broker for getting a good deal on stamp duty or PLCs?