On this edition of Property It's Hot, we review a cutting edge 3D-construction technology called building information modeling (BIM), which promises to get projects delivered on time without cost overruns. Also, we uncover a few factors which explain why South Chennai has overtaken the North of the city in real estate. On our Smart Advice series, our experts discuss what property buyers can do if their builder refuses to refund their booking amount in the event of a cancellation.