The devil is in the details and I'm collecting some details that may disappear. In the past few months, when I remember to do it, I have been collecting images from one of the District of Columbia databases. These are exterior shots of houses taken in 2004. It is now 2014, ten years later and so I'm concerned that government may update these images. 2004 is a good enough year for my purposes. Considering that at that time not a lot of houses underwent a lot of changes, many have remained unchanged and look pretty much the same. But some others, with the rise of real estate prices, had additions placed on top ("pop-ups"). It is good to have a resource to see houses prior to possible changes.

Link- DC GIS Master Address Repository