Tip for dating a door and outside upgrades: Google maps includes historical street view data, and Google Earth on the desktop (not your phone or tablet!) allows you to do the same with satellite photos.

I was able to date the age of the roof in the place we are buying to a few-month window because the new roof was present in a Google Earth satellite photo but was not present in a street view pass a few months earlier. Also was able to date a bunch of outdoor upgrades and landscaping because a satellite capture happened to show the crews installing them.