Under-construction properties are a gamble even with RERA.

I'm looking at Noida for investment property, specifically around Sector 105. I've bought two ready-to-move flats before, but the prices are high now. I'm tempted by the lower prices of under-construction, but I'm hesitant. Aashi Construction Infra has a project there. Is it worth the risk? Have you guys had good or bad experiences? Possession delays are a nightmare, right? Or should I just stick with ready-to-move? What are your thoughts on the ROI?