1. It is pertinent to have the original title document for further transactions.
If you dont have the same, you may lodge a police complaint about the missing document, publish the same as a public notice in any local newspaper, obtain non-traceable certificate from the Police.
After that along with all the said documents, you may apply for copy of certified registration copies of the document before the SRO's office.
2. Succession certificate is different to that of the legal heirship certificate/family tree certificate.
It is not mandatory but the buyer may insist on it.
3. The parties to this may even execute a registerd POA in your favor if they want to avoid visiting the registrar's office.
4. The stamp duty paid by your father was for registration of the same to his name, hence you may have to pay the stamp duty afresh for the prioperty you are likely to acquire now.
The applicble stamp duty and the registration charges may be enquired locally.
5.Income tax in this regard may not be applicable if you are the beneficiary.