Under-construction projects in Delhi are a huge risk

Visited an Aarone Group project in Bhera Enclave last weekend, and honestly, under-construction lena ab samajh nahi aa raha. Sales rep ne bahut high hopes di but site pe progress dekh ke darr lag raha hai. They're promising possession in 18 months, but I've heard so many horror stories about builders delaying delivery. My parents keep saying only ready-to-move lo. Plus, initial quote mein maintenance aur PLC ke charges aise chhupaye hue the, I had no idea. Is it normal for builders to be so vague about total costs until booking? Anyone else faced this with Aarone Group in Delhi? How do you guys evaluate delivery risk for under-construction projects?