misterspock wrote:The autograph is really tough to quantify. I've seen the run-of-the mill PHB 6th prints and DMGs later prints that have Gary's autograph go sometimes relatively inexpensive (approx $30-$50) and sometimes towards $120-$180. However, the higher end ones were early/1st prints of the DMG or PHB.

I would generally figure the Gary autograph could add about $15-$30 ontop of the actual value of the book. However, the fact that your book actually came from the first batch sold at that GenCon AND has the specific signature to prove it I think adds even more value. It's hard to tell the condition of the book from the photos (are there any other notes or scribbles, marks, stains in the book?) I'd figure if the book is in good condition, you could start out the bidding at $75-$100 and see where it goes. I think there's been a Gary-mania sweeping through over the last year so I could see it doing well.

btw, getting further autographs I think could add some value. Maybe figure $10 per signature, that would be my guess.