The Supreme Court on Wednesday directed real estate major Unitech to refund the principal cost of flats to 39 buyers who had booked apartments in a Gurgaon project seven years back and have still not got possession of their houses.Directing Unitech to refund the principal amount, a bench of Justice Dipak Misra, Justice Amitava Roy and Justice A.M. Khanwilkar said the question of interest and compensation for failure to deliver the possession of flats would be considered at the next hearing of the case in the second week of January next year.While passing the order, Justice Misra said Rome was not built in one day and the foundation of any economy was the "faith" that a buyer reposed in the seller. The court, in its order, noted the agony of the buyers as they told the bench that even after paying the entire amount they were still without a roof of their own and were living in rented accommodations.