Speaking to Mirror Money, Matthew Haley, head of books at auction house Bonhams, explained: “Bonhams sold a set of first editions of the Harry Potter books in 2005 for £14,400, and on two occasions in 2007 sold copies of The Philosopher’s Stone for £9,000. That first book in the series is worth hugely more than the subsequent volumes, and condition is everything. More recently first editions of the first book in fair condition have sold for around £4,000. Obviously genuine signatures or even better inscriptions by JK Rowling can add tremendously to the value.”
As the book series goes on, the less the first editions are valued – novels after Chamber of Secrets range from around £1000 down to less than a tenner – in that order. This is simply because of the sheer volume that was produced due to the ever-increasing popularity of the series as it went on.
The first two books are of particular interest, so readers should look out for the “Joanne Rowling” credit in Philosopher’s Stone alongside the print line “10 9 8 7 6 5 4 3 2 1.” As for Chamber, it was published in 1998 and the first copies can sell for over £1000. Early versions of the deluxe editions also make thousands, while standard early print versions sell for a similar price.