The focus is on strategy. A unique set of circumstances allows a unique comparison. Since the results of such an investigation are least applicable to other circumstances this is the least preferred approach. The intial stage is to do some research. Note that projects for which the ARR is actually run by the university library system and that the working drawings are owned by the Syracuse University Library system.
Documentation Carefully examine the working drawings.
Often sheets are missing and the investigation may have to be adjusted to account for missing data. The working drawings and the buildings do not often match. Buildings get changed in the course of construction and, of course, after they have built. You should know the building as thoroughly as possible from the drawings before you visit the actual building. Carefully examine the building itself.