As said, good luck to the seller but maybe 12K would of been got around 1996/1997 once the band reformed with Peter and Ace and the hype was at maximum.
Maybe it's worth 12K - I know Stu from Queensland got offered 10K for his and he declined
Maybe if Eric Carr was the drummer (the Fox Rox 1950-1991 R.I.P.) was on the game it would be worth more
I honestly believe that when KISS disband - the pin will be worth "bigger" money. Same with Hugh Hefner. Playboy and KISS will be "unaffordable".. If I told you how much I've been offerred for one of my fully restored KISS (with IPB playfield), you simply would not believe me.
It is not about the pinball - it is about the theme.