'Antiques Roadshow' guest says 'that's insane' after hearing the value of his Roald Dahl signed book

Books are an essential medium for ideas and stories of one era to be passed down through generations. "Charlie and the Chocolate Factory" is a book that hasn't just gained iconic status in literature, but has also been adapted on screen multiple times, and is celebrated author Roald Dahl’s most popular work. The book came out in 1964, and a signed copy of its first edition turned up on "Antiques Roadshow."
A guest named Tim brought it on “Antiques Roadshow” and claimed that he received the book from his mother, but had no idea where she got it from. He was also unsure of whether his copy truly was a first edition. The best part of the book was the small note written on the front page and signed by none other than the author himself. The item's value was so unexpected that the guest called it "insane."
“To Steven, with lots and lots of love, from Roald Dahl,” the note read. The author even wrote a date along with the note. When the expert asked the guest who Steven was, he said that his research attempts did not bear any fruit. “I asked myself that exact question,” he said. “I actually was like, on the internet to be like, 'Is there a Steven Dahl?’ I was like, maybe it’s a relative of something,” he said.

While Steven's identity remained a mystery, this copy of Charlie and the Chocolate Factory indeed was a first edition print. The expert took various clues into account while ascertaining this. Firstly, the copyright page of the book should have six lines printed and not five. Secondly, there needed to be a price on the dust jacket. The final thing to look for was an International Standard Book Number (ISBN) on the rear flap of the dust jacket.
Tim’s book met all the criteria. “Your book has all the salient points to be a first edition of the children’s classic,” the expert revealed, much to the guest’s pleasure. Turns out that there were roughly 10,000 of these first edition copies that ever came out. One could notice that this copy of the book was not just for show. The guest had read it multiple times as a kid, and there were signs of prolonged use.

The dust cover had little nicks and tears all over, which played a detrimental role when it came to the book’s valuation. When it came to the appraisal, the expert said that he’d place a retail figure of $5,000 to $6,000. The guest wasn’t expecting this and said, “Wow, that is crazy. That is insane.”
The expert also said that if the book were in perfect condition without all the small damages on the dust cover, it could bring in between $9,000 to $12,000 in a retail setting.