It’s a custom-built house with a backyard pool on a whopping wooded lot. Large rooms, a spacious floor plan, and a fantastic fireplace should attract lots of interest. So why isn’t it selling? We hold our hidden-camera open house, and the vote is unanimous–the house is a throwback to the 1970s. The basic plan: Update the living spaces with fresh paint to highlight the architecture, remove clutter, and add some much needed class. Can we turn this ’70s A-frame into a clean, up-to-date retreat?