How do you identify a first printing of Japanese Vagabond?

Japanese publishing makes this easier than English collectors expect. Every Morning KC volume ends with an okudzuke, a colophon page that lists the book's printing history in plain type: the date of the first printing, and the date of the printing in your hand. A true first printing of Vagabond volume 1 reads as a first printing dated March 23, 1999. A fifth printing says fifth, with its own later date. The book confesses; you only have to turn to the last page and read it.

What the colophon does not reward is shortcut-hunting. ISBNs are shared across printings, obis are advertising, and condition is a separate question from printing. The five checks below are the order this shop works in.