Urgently need help 2

i have a godown in kolkata 50 years . we have it for about 50 years . now the landlord does not give us the bill and takes a monthly rent of rs 400. now suddenly he is saying that the rent be increased to rs 1500 and also pay a salami of rs 2 lacs. after which they are saying they will give the ownership to me. now i dont understand one thing that if i give the salami then i become the owner of the godown and if it is so then why shall i keep on paying rent to landlord. also kindly enlighten me on what are the benefits and backdrops of the ownership procedure as suggested by the landlord in respect to me?