RERA checks: What the website won't tell you

Builder's legal track record is the first thing I check, no matter what. I'm looking at some projects in Mohali and New Chandigarh, maybe even Manohar Singh and Company. But RERA registration kaise properly check karein? Matlab, website pe toh sab dikhta hai, but hidden red flags kya ho sakte hain? Aur agar koi builder jaise Saini Bhawan mein issue ho, RERA complaints actually effective hoti hain kya? Yaar, my parents keep saying due diligence bahut zaroori hai. Any experiences with builders and RERA compliance here?