Originally posted by H. Sapiens The other lesson is the K3II most likely didn't sell well in Japan or there would be more second hand bodies on the market.
Not necessrily. Most K-3 II buyers were Pentax fans in general and the K-5, K-3 series in particular, who bought a K-3 II to upgrade a K-5 or to get pixel-shift. When the K-3 II was released, the K-1 had already been announced, so there should be no K-3 II buyers that decided to trade it in for a K-1 later. Most of the K-3 II buyers have no reason to replace their camera, it's only been three years.
It is likely that very few K-3 II's were being sold when production was ended and you might still be right that the K-3 II didn't sell as well as expected, but a lack of second-hand bodies isn't an indicator. The KP was originally promoted as a special edition for fans of Pentax film cameras, like the Super Program; the first we heard that it would be the flagship APS-C was after Ricoh changed its CEO and every division was put on lockdown.