Preferably, yes you should consult a lawyer before you purchase any property. It is not really necessary to have a lawyer during the negotiations unless you are making a very huge investment. However, you should crosscheck and verify the documents and the legalities with a lawyer before you make your down payment. A property lawyer or a conveyancer deals with the legalities related to real estate and property purchase. If you are purchasing an apartment or a flat from a builder, then they will have a lawyer to prepare and notarize the documents. You need to collect the land deed, sale agreement, building plan, EC, and other vital documents from the builder or the individual seller and show them to your lawyer. The lawyer will research into the property details to find out if there are any legal issues associated with it. The lawyer will also check if there are any other issues with the documents or certifications, so that there are no problems when you purchase the property.