Hi,
1. We recommend you to do the registry at 25 lacs so that all the money comes in white
2. If you are selling the property at loss, no capital gain tax will be attracted. However you have to show the transaction in your return.
3. Refer point 1.
4. You need not pay tax
Please feel free to call/ revert in case you need more clarity
Thanks and regards
Abhishek Dugar
CA CS B.Com