The owners of a split level in Demarest didn’t want an open house. So, Risa Corson of Coldwell Banker Real Estate’s Closter/Alpine office set up appointments, over three days, for three hours each day. Sixty people toured the home and more tried to get in but were turned away because they didn’t have an appointment, she said. “Every one said they had never seen a house so well maintained,” Corson said. “It was bright and airy.” Though well kept, the home didn’t have a modern kitchen or bathrooms. But it is “on a lovely street and had enough yard.” Corson had been in touch with the sellers for …