Mohali pre-launch offers are often just marketing

I'm kicking myself for not buying a 3BHK earlier in Mohali. Currently in a 2BHK, but looking to upgrade to a bigger 3BHK or maybe a villa around Sector 102. Prices have just shot up, it's crazy. Pitrachaya Buildwell has some projects, but I'm honestly not sure if their 'pre-launch' offers are even good deals anymore. Are builders actually open to negotiation in Mohali these days? Like, how much can you realistically push for a discount on a 3BHK costing 1.8 Cr+? Also, what's smarter for an investor – a construction-linked payment plan or just a bigger down payment for better terms? I've heard some builders give better rates for upfront cash. Any experiences?