High stamp duty on registered rent agreement how to go about it

Hello sir I need to consult that we are going to make a Rent agreement for 15 years. And as per law any Rent agreement should not be more than 11 months if it's just notarized. But I need an registered agreement and I have been informed that if I do that then I have to pay stamp duties either on property value or on Rent decided for per month. But Sir both are a heavy amount to be paid and I am not weeling to pay that. So kindly advice me that what should I do in which I get a lawfull documents so that I should not be facing any issues by our landlord in future. And without investing or paying huge stamp duties. And I am investing a huge amount on interiors on that property. So kindly advice me a lawfull way. Which should secure my investment on that property. Hoping to hear a positive advice soon. Thanks&Regards