Yes and No. When I got into pinball seriously $4200 was the price of NIB Stern and everyone thought it was getting out of hand then.
The guy in the Sorcerer thread is making his own bed there but hats off to him because he's holding his own. Even if its delusional 
Some topics on pricing...
https://pinside.com/pinball/forum/topic/stern-prices-going-up
https://pinside.com/pinball/forum/topic/future-of-pinball-prices
https://pinside.com/pinball/forum/topic/will-prices-ever-go-back-down
https://pinside.com/pinball/forum/topic/retail-prices-are-they-crazy
https://pinside.com/pinball/forum/topic/new-to-pinball-collectingare-these-prices-for-real
https://pinside.com/pinball/forum/topic/how-are-house-prices-where-you-live-theyre-crazy-in-new-england
https://pinside.com/pinball/forum/topic/stle-are-prices-going-up-or-are-sellers-just-dreaming
https://pinside.com/pinball/forum/topic/where-will-prices-stabilize-for-medieval-madness-after-remake-run
https://pinside.com/pinball/forum/topic/prices-about-to-come-down
https://pinside.com/pinball/forum/topic/do-nib-prices-fluctuate-over-time-is-it-better-to-wait
https://pinside.com/pinball/forum/topic/new-stern-prices
https://pinside.com/pinball/forum/topic/increasing-prices-good-for-pinball
https://pinside.com/pinball/forum/topic/increasing-prices-terrible-for-pinball
https://pinside.com/pinball/forum/topic/what-am-i-missing-about-some-of-these-prices
https://pinside.com/pinball/forum/topic/has-high-prices-influenced-your-pin-purchases
https://pinside.com/pinball/forum/topic/are-mr-pinball-2016-prices-too-low
https://pinside.com/pinball/forum/topic/if-you-want-to-cry-about-prices-look-at-this
https://pinside.com/pinball/forum/topic/my-game-is-worth-top-dollar-have-you-seen-the-prices-
https://pinside.com/pinball/forum/topic/pinball-machine-prices-1
https://pinside.com/pinball/forum/topic/used-pinball-prices-what-is-going-on
https://pinside.com/pinball/forum/topic/em-pinball-machines-prices-on-the-way-downon-the-way-up#post-4240585
https://pinside.com/pinball/forum/topic/is-jjp-pricing-itself-out-of-business
The great price bubble debate...
https://pinside.com/pinball/forum/topic/stern-prices-going-up
https://pinside.com/pinball/forum/topic/the-bubble-in-pinball
https://pinside.com/pinball/forum/topic/why-pinball-will-battle-on-and-survive
https://pinside.com/pinball/forum/topic/this-is-not-a-rebirth-of-pinball-its-a-bubble
https://pinside.com/pinball/forum/topic/pinball-manufacturers-creating-price-bubble
https://pinside.com/pinball/forum/topic/pinball-price-bubble-will-pop
https://pinside.com/pinball/forum/topic/pinball-price-bubblenotice-some-strange-things-here-in-the-north-east
https://pinside.com/pinball/forum/topic/pinball-price-bubble-mm-as-an-example
https://pinside.com/pinball/forum/topic/pinball-price-bubble-think-it-cant-happen-think-again
