In 2007 I attended the Matthews auction that was held just over the Miss. river from St.Louis in Collinsville, Ill. This is the year the Harbor sign sold for over $60,000.
I don't know how this compares to the values of the signs stated above (I am not a sign person), but I do know if you love signs this is the auction you should have attended.
I didn't take as many pictures as I should have, but I believe these pictures should wet your whistle.
Question, if in 2007 the Harbor sign sold for $60,000 what now is the highest price ever paid for a sign at a auction. Who knows what a sign sold for in a private sale?http://petrolianacollectibles.com/matthew.htm
(click on the pictures for a larger view.)