What builders don't tell you during site visits

Under-construction projects in Greater Noida feel like a huge gamble right now. I'm checking out some 2BHKs in Sector 18, including a Royal Next Homes project. Honestly, my biggest fear is the delivery delay and all the hidden costs. Parents bolte hain ki registration, stamp duty, interiors mein bahut kharcha aata hai. Kya ye sab property price ke upar bahut zyada ho jaata hai? Anyone who bought recently, kitna extra budget rakhna chahiye for these things? Aur site visit pe kya kya dekhna chahiye jo builder nahi batayega? I mean, beyond the fancy model flat, what are the red flags? Basement parking, water pressure, lift quality – kya cheezein important hain check karna? Royal Next Homes ka delivery track record kaisa hai? Ab samajh nahi aa raha kaise evaluate karu delivery risk, especially with all the news about market slowdown.