Empty nester's dilemma: New flat negotiation or resale?

Is it better to push for negotiation on a new project like The Hemisphere in Noida Extension, or explore secondary market deals? Kids have moved out, so I need a compact 2BHK, manageable for us. Builder quoted ₹85L for a 2BHK, but I'm worried about hidden charges later. Should I try to haggle hard, or is resale property generally more transparent with all-in costs? What do you all think is smarter for someone my age?