This is a house in Weselberg, Germany which I used to live in 20 years
ago: http://www.weathergraphics.com/tim/wes94a.jpg .
Using "standard" dimensions for German exterior doors and ceiling
heights, and a basic geometric analysis of this photo, can you
estimate the dimensions of this house?  I am trying to make a
floorplan for my memoirs.  The toughest part is estimating the depth
using some sort of geometric relationship for perspective.  Camera was
a throwaway Kodak 35 mm, and print was scanned.

I would contact some realtors located close to the house.  They might
be able to tell you or tell you where.  Or, if you have the address of
the house, find out the phone number and call the present owners (if
the house is still there and inhabited).

that should read: "tell you or tell you where you can get that info"