I was very lucky to find this Royal KHM Standard at a local antique shop for $50.  I tested it out to make sure at least the keys didn't stick and I would be able to type on it.  It was in great condition for its age.  It typed at first and I noticed holes and rips in the ribbon and later realized that either the ribbon was bad, or the platen may be too hard.  The platen seemed ok.  I put a new ribbon into the existing spools and they wouldn't move.  Thanks to comments left to me on this problem on Typewriter Talk, I was able to fix that problem by properly inserting the ribbon.  I love typing on it, has a great touch and the type is clear and even.  I can't find the serial number on it but what I have read online at numerous sites its possible this one may have been made in 1937 or earlier.  I didn't know where the margins were to set and discovered a video created by a teenager who had purchased the same machine and he gave a great demonstration.  I learned every aspect of the machine's capabilities.  I just love typing on this piece of history.