Starting from the corners of the walls, measure across to the first window, door, wall passthrough or doorway. Be sure to include the door or window trim in the measurement. If a doorway or wall passthrough has no trim, that would obviously mean to the opening itself. Next, measure the width of the window or door from outside trim to outside trim. Next, measure from trim to trim to the next obstacle and so on, until you reach the opposite wall. Then take an overall measurement from wall to wall. Repeat this for each wall. If there is a peninsula wall midway in a continuous wall, measure that separately from where it starts perpendicular to the running wall, then length & height. Measure overall ceiling height from finished floor to finished ceiling. Measure all plumbing centers from perpendicular walls. Measure heights of windows to include trim and distance from floor to bottom of window trim, Measure heights of doors to include trim (if applicable). Finally, measure and indicate widths of window & door casings (trim), baseboard molding height and crown molding height (if applicable) from ceiling down vertically.