1. it is mandatory to obtain probate of the will in the presidency towns namely Kolkata, Mumbai and Chennai.
Therefore to enforce will you can obtain probate.
If there are only two legal heirs to the deceased and your sister is willing to relinquish her rights, then you may get a registered release deed execute by her in your favor relinquishing her rights in the property.
This will help you tide over the crisis to pay the stamp duty to get the will probated by avoiding the subject probate itself.
2. The market value of the property as per the government guidelines will be taken into consideration.
3. The city civil court if the value is within its pecuniary jurisdiction.
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4. Enquire it locally since it is a local subject.