Pre-launch deals are rarely true discounts

Budget finalised, loan pre-approved — now stuck on which sector. I'm looking at places in Greater Noida, specifically around Sector 157, maybe something by Aashi Construction Infra. My parents keep saying to go for pre-launch offers, saying it’s cheaper, but honestly, I'm not sure if that's true. Is the 'early bird discount' just marketing? Or does it actually save money compared to buying later? Also, what's better for a first-time buyer like me – a construction-linked payment plan or just paying a bigger down payment upfront? I'm worried about getting trapped with hidden costs later on or projects getting delayed. Any experiences with these payment structures or if pre-launch is genuinely better for ROI near Jewar Airport? Not sure how to compare the real all-in cost with these different options.