How do u check the legal papers of a property that u are purchasing(ex flat)?

I apologize, I am not real sure how it works in India, but in the states people who are considering purchasing a piece of property use an Escrow company which does a title search to make sure there are no other liens or encumbrances on the property. Often times people also purchase title insurance which will defray the expense of any litigation that may take place to get clear title to the property. Even in India, I would suggest you hire someone to do a title search to make sure it is a clear title. If you can't get a clear title to the property don't buy it. Someone may have taken out a second and if you purchase the property without a search you could end up paying for the other person's financing. Be very careful.