Noida investment: The rental yield reality check

Okay I'll be honest — I'm completely confused about Noida property investment. I'm based in Dubai and can't easily visit. I'm looking at 2BHK flats near the upcoming Jewar airport, thinking of the ROI. Has anyone actually achieved the advertised rental yields? I'm seeing ads promising like 6-8%, but is that real? Kya scene hai? Also, is it better to buy under-construction from a builder like Lotus Greens, or go for ready-to-move in Naya Gaon? I'm worried about possession delays. Need a property manager too, any recommendations? Honestly not sure if it's worth the risk investing remotely without seeing it myself. Should I just stick to FDs? Please advise!