From advising clients to buying my own home

Been in this market for years, helping clients, but buying for myself in Greater Noida is a whole different ballgame. I'm looking at Sector 77, checking out some Shree Brahma Infraheights projects. Builders always push pre-launch offers, saying it's the best deal. But is it really a discount, ya just a marketing tactic? I know the super area vs carpet area games they play. Matlab, kitna difference expect karein between the two? Honestly, for a 2BHK around ₹70-80L, after all the PLC, OC, parking, is the *actual* per sqft rate still value for money? Kya secondary market mein better deals mil sakte hain, ya new projects hi sahi hain for long-term appreciation, especially with the Jewar airport buzz? Any insights would be super helpful.