If you do the math, 65 times, it amounts to more than $180 million: a handsome sum for an offhand find and well worth continuing to court experts over, even in the face of expert dismissals and disavowals. When the Van Gogh Museum rejected the sketchbook outright in 2008 — calling the works “monotonous, clumsy and spiritless” — the owners simply sought more opinions until they found one that fit.