Hi,
1) 20,000 per decimil. Seller will pay the tax.
2) Get the new PAN card according to Aadhaar and then link it.
3) 45,000 per decimil. Section 50C.
4) I think RERA is for registration of projects by the builders and developers. Take second opinion.
5) Take concerned advocate opinion. Can ask on indiakanoon.com
6) No such procedure.
Thanks