You're looking to buy land where the seller's late husband held the original title from 2015, acquired through general possession. After his passing and a release from their sons, the seller inherited rights. To proceed safely, it's crucial to examine the 2015 document for any prior ownership details and obtain an Encumbrance Certificate (EC) for the last 30 years. Consulting a senior lawyer is highly recommended to scrutinise all deeds, including the patta, and ensure the title is clear and legally sound before purchase.