Checking RERA registration isn't as straightforward as it seems

Checking RERA registration isn't as straightforward as it seems. I work in real estate but buying my own place in Sector 65 is making me super careful about legal stuff. How do you *really* verify builder RERA registrations beyond just the number on the site? I'm eyeing some Adani Realty projects and need to check their track record properly. Is filing a RERA complaint actually effective when builders delay, or is it mostly just on paper? What specific red flags should I look for in the builder-buyer agreement that favour only them? Any insider tips would be great.