While purchasing a building or apartment from a builder/developer, be sure about certain things: 1) The land where the building/apartment is planned to be built should not be an agricultural land. It should have converted to residential plot and the layout should get approved. 2) Confirm all the necessary documents of the land for any mortgages or legal issues and confirm whether the builder/developer has paid tax for the land or not. 3) Check for all necessary needs like water, electricity etc are available in that area, else it will be on you to get the connection for your building/apartment which will cost you much.