That is one of the most dumbfounding things I've seen in a very long time!
The bulk of it is made from post war (late 1940s) Czech shelter quarter material. It's beat to Hell, obviously, but repaired with SS and WH cloth. That's really strange.
The cut isn't like anything else I've ever seen either.
I don't know what to say about it, other than it's not worth nearly what the guy is asking for. Not without some evidence that it's special. Even then, given the condition, it's got some big strikes against it.