1. inform the bank and find out the possibility of transfer of the loan in joint names or your name alone, get an NOC from the bank and go for a gift deed.
2. The transfer will be absolute and the stamp duty in your case shall be 2%, and you will not have to worry as the gift deed is the safe and less expensive in terms of stamp duty.
3. As per the Maharashtra stamp Act, the stamp duty payable on a release deed is (a) Rs.200 if the same is in respect of ancestral property and the release deed is in favour of the persons named in the applicable Article, or (b) in every other case, 5% of the market value (ready reckoner value) of the property. Since the property is not ancestral property, for a release deed, the latter will apply.
4. Thus from a stamp duty perspective, it is advisable to execute a gift deed rather than a release deed