Original price: $21.3 million (2007)
Inflation-adjusted price: $26.1 million
A copy of the Magna Carta was on the auction block, and not in a museum, in 2007. Billionaire co-founder of the Carlyle Group, David Rubenstein, alarmed that the historic (but not quite priceless) manuscript would end up with an owner overseas, decided to plunk down a $19 million bid for the copy (including fees and commissions, the final cost was $21.3 million). Rubenstein, who also uses his $2.8 billion net worth for philanthropic efforts, put the Magna Carta back into the National Archives.
It’s unknown how many copies of the Magna Carta were made, but it’s estimated there were maybe 250 copies made. In 2015, an original copy of the Magna Carta was found in an old scrap book in a British coastal town (it’s speculated to be about $15 million, but it hasn't been put up for sale so its actual worth is unknown).