NRI's Noida Ext dilemma: builder delivery & hidden costs?

Godrej, ATS, Gaursons ke projects mein actual delivery timelines kya hain Noida Extension mein? I'm based in Dubai, so cannot visit frequently. Worried about hidden charges at possession, like extra maintenance deposits ya PLC. Kya builders like ACE Group ya Mahagun bhi last-minute surprises dete hain? Aur customer support after booking, kaisa hai? Do they actually pick up calls for remote buyers ya ignore karte hain? Seeking honest experiences near Sector 150.