CRZ3 norms Neelankarai Casuarina drive and Sunrise Avenue

Q: Hi,
I wanted to get clarification on something related to the CRZ regulations in these areas, Neelankarai Casuarina drive and Sunrise Avenue. I am looking at plots to Construct a residential house for my family.
G+1 as here it only 0.8 FSI.
Question 1: Has Neelankarai come under the CRZ 3 - Category A where the No Development zone is 50m? or is it 200m?
Question 2: In a no development zone would we be allowed to Construct a G+1 house, I am seeing lots of villas and plots being sold as unapproved and brokers are saying its not an issue if we get a Municipality and Corporation approval to construct the house as per the 0.8 FSI, is this correct?
Question 3: Can anyone refer a good consultant who would be able guide me on what the necessary legal requirements we need to adhere to in these CRZ3 areas?
Thanks,
Arun