Faridabad upgrade: Legal worries before I commit

Since January I've been eyeing 3BHKs in Greater Faridabad, planning to upgrade from my 2BHK in Sector 15. The prices for places like Goyal Luxury Floors are quite high, around ₹1.2 Cr, so I'm doing full due diligence. Honestly, builder ka track record aur RERA compliance ko leke bohot tension hai. Pehle suna hai ki kuch builders ka legal history theek nahi hota, aur title verification mein bhi issues aate hain. How do you guys actually check RERA registration beyond just the number? What about title clarity, especially for new projects near the DM Expressway? Is Goyal Estate Agency ka past clean? Any red flags to look for when checking a builder's legal background? Don't want to get stuck later, already have one home loan.