Landscape contractor Roger Cook installs 200 running feet of pre-cast concrete to create a retaining wall that will define the perimeter of the new backyard. Inside the house, wallpaper historian Richard Nylander helps host Kevin O'Connor date and evaluate the historic wallpaper throughout the house, while general contractor Tom Silva frames for a new window in an old wall. Kevin makes a trip to Cambridge, Massachusetts, to see how three 19th century buildings are being moved as part of a construction project at Harvard Law School. The million-dollar move, which has been planned for five years, requires the buildings to be lifted and rolled down Massachusetts Avenue on hydraulic dollies steered by remote control.