From 2BHK to villa – my honest upgrade story

Not proud of this but I almost got duped by a pre-launch scheme. I'm currently in a 2BHK near Whitefield, thinking of upgrading to a 3BHK or maybe even a villa in Prestige City. Already have a home loan, so this time I really wanna be careful with legal stuff. Bahut confusion hai. How do you guys actually check RERA registration details? Matlab, just the number is enough, ya aur kuch red flags bhi dekhne hote hain? Aur agar builder like Prestige Group delays possession, RERA mein kya real options hain? Is it actually effective or just on paper for compensation? Also, builder ka legal track record kaise verify karte hain? Koi specific documents ya sites hain jahaan yeh sab milta hai? Don't want to get stuck again. Any advice on protecting myself from legal traps would be super helpful.