For my opinion the price for this unsigned book 1751.00$ was exorbitant to high!!
I would say the price should be:
Unsigned 800$ - 900$
Signed 1200$ - 1400$
Depending on the status of the book!
This is my opinion, based on the price they where sold the last three years.
But as NOBUDY is replaying my thread with some real price suggestions for both versions, it is all only speculation from my side!! 
ALF