Transfer of name in a pagdi system property

Hi,

We live in a pagadi system house and we had brought the house in 1969. It is in the name of my grandfather. He expired in 2007. Now, ie after 5 years, the landlord has asked to pay Rs. 5,00,000 for transferring the name of the house im my dad's name. We are not that financially stable at the moment. Is there any way we can avoid paying this? Also he has stopped taking rent from us until we tranfer the name. What should we do? Kindly advice.