Under-construction projects always hide costs

Spent Sunday checking options in Sector 151A, including V5 Group projects. 2BHK pricing sounds okay, but honestly, *actual* total cost ka idea nahi. Builders quote basic prices, right? Stamp duty, registration, interiors... kitna extra lag jaata hai? My budget ₹78L, parents bolte hain ₹90L cross karega. Anyone bought under-construction in Greater Noida recently? Share real cost breakdowns. Under-construction projects mein delivery risk kitna hota hai? V5 Group ka track record kaisa hai for timely possession? First-time buyer hoon, darr lag raha hai delay na ho jaaye. Builder-buyer agreement mein kya red flags dekhun? Advise.