I believe I've found a bug: Buy an Urchin at the very end of your turn, and then *don't place him*. On your next turn, the price for an Urchin is now +1, even though you *didn't* buy an Urchin this turn.
That's not a bug (though the game doesn't do a good job explaining this) - it's meant to discourage "urchin hoarding" (also "thug hoarding") where you all of a sudden swamp the board with characters your opponent wasn't able to see coming and therefore couldn't counter. (Originally, the game didn't work this way, but after a bunch of internal play testing we changed the rule because that strategy was no fun.)
Oh, I see. The text in the box should certainly be updated then, because it currently implies that the reason for the higher cost is that one was hired this turn..