sir i want to know that my grand father purchased land 40 year ago at that time he did not got sale letter and he did not register the land

sir as all the connection related to water, electricity, etc were started in the name of my grand father, and we are also paying house tax, elcetricity, water etc tax for the last 40 years, and we do have register our name in the municipal department,

sir how i can do the registery of my house please give me advice