(2D work flow question, probably applied to 3D as well). Has anyone worked up a best practices presentation for dealing with existing construction, demolition, drawings, and new construction? I've tried several methods, and nothings seems to be as simple as it should be. I end up creating Existing, Demo, and New Layers for each level of a building. I create Existing, Demo, and New Wall Types. I create Existing, Demo, and New Classes for 2D objects.    Autoclassed objects like windows a