Under-construction projects are a pre-launch pricing trap.

Kya under-construction projects mein invest karna ab bhi worth it hai, ya pre-launch prices just a trap hain? I'm looking at a 3BHK near Kokapet, maybe My Home or Prestige. Builders claim early bird discount but then construction delays aur hidden costs add ho jaate hain. RERA ka protection kitna real hai, I'm not sure. My past experience with Salarpuria Sattva was okay, but ab market itna competitive hai. Is it better to just pay the premium for ready-to-move in Gachibowli, even if it's 20-30L more for a similar 3BHK? What's the real ROI difference, considering immediate rental income versus potential appreciation from UC? I've seen some projects in Narsingi, but OC issues ka bhi darr hai. Should I just wait for RTM?