Quoted from pinsanity:

As long as manufacturers keep raising the entry fee for the new machine market then used machine prices will continue to keep pace and rise in value.
Here is the typical scenario I hear on a daily basis when conversing with new buyers:
Most new entrants to the market just want a feature complete full sized pinball machine for their gamesroom - when they do some googling and see the entry level pricing in Australia for a new machine is $8250, then all of a sudden a used refurbished and redecalled Getaway/Fish Tales/Judge Dredd for $4000 doesn't seem all that unreasonable. They are quite happy to pay that price for a now 25 year old machine provided it is shopped out and most importantly fully working when it leaves my premises and they take possession of it.
Remember these are not your hard core pinheads who are willing to max out credit cards to get that 30 second NIB endorphin rush 2-3 times a year. They just want a working machine to put in their gamesroom next to the pool table and the 60-in1. If that eventuates to a second machine or even more then all good, but I predict given the pricing that the number of new single used machine owners are far outstripping total NIB sales across the board at least in Australia. This is from the twenty year sales high back in 2012 when ACDC had the price point sweet spot on NIB sales (under 6k for entry level and change from 10k for an LE) and ops were actually buying Pro machines hand over fist to put on location. How they managed to screw local sales up in just 5 years to a fraction of what they are now beggars belief but I lay the blame solely on entry point pricing and essentially abandoning one of the legs of their core business: operators.
I feel the pain of the ever shrinking pool of current new in box buyers and have virtually halted buying NIB machines myself as a result of pricing, but from a purely business standpoint as a used machine container importer I hope the trend continues as it justifies the intitial upfront outlay and the market down here is still expanding with new entrants every day just not via NIB machines.
Personally from what I see and hear the used machine market is less about supply/demand principles (with a big enough chequebook there are very few machines that I have been unable to locate from anywhere in the world) and more about the fact that entry level pricing on NIB machines is becoming too much for the "average joe" new entrants to even contemplate.

Quoted from T7:

Chicken and the Egg -> both are true. Higher NIB pricing IS pushing prices up *AND* enough people are paying it, so the prices keep raising.
It really all started with JJP having the new "vision" of a premium pinball company selling games at $6500 when current NIB games were less than 4K. The market has been playing leap frog with NIB pricing on "premium/LE/CE" games since then.

Quoted from jar155:

New money has really helped to buoy the hobby and stabilize a shaky time for the manufacturers, but man, the new money collectors have really been a huge buzzkill to have around too. They've caused as many problems as they've helped to resolve, so I still don't know how appreciative I am of the new money influx.

Quoted from jar155:

I know this comes across as "angry man shouts at cloud" in many ways, but man, for those that were around 10 years ago, the current scene in pinball can be really frustrating when dealing in the secondhand market. You have so many self-proclaimed experts that have less flips under their belt than my 5-year old that are all too eager to make their bold statements on pinball and pinball pricing. New people in the hobby are great, but loudmouth newbies with big wallets are often a bit tough to handle. From my "Pinball has Been Gentrified" article:
"If not for the money infusion brought into the hobby by the new blood pinball machine collector, NIB pinball could very well have died off. With operators decreasing in number, NIB sales weren’t exactly healthy just a few short years ago. Today, each new release has a willing and ready buying audience, and games are selling in numbers that are more in line with pinball’s better days, even with the prices of current games skyrocketing. I do appreciate being able to see a steady stream of new games.
But the lack of taste, tact, respect, and knowledge that many of these new bloods bring makes dealing with them hard. These new collectors value theme and collectible nature over gameplay and fun factor. When a new game is being announced, these new collectors tend to value the theme first and foremost, the art second, the sound third, the number of LE versions produced fourth, what others will think of their purchase fifth, what video clips show up on the LCD sixth, how many layers of clearcoat it has seventh, and a few other things before we get down to questioning whether or not it’s any fun at probably a distant 12th. 
The new blood collector has a pinball memory that extends back to Stern’s Lord of the Rings at the earliest, with some passing knowledge of the “A list” games from the late-era Bally/Williams catalog. Despite this fundamental lack of pinball knowledge, they’ll be the first to tell you all the reasons why LCD displays are a true “game changer for pinball” and playing any games with DMD, alphanumeric, or *gasp* mechanical reels, is a giant waste of one’s life.
The new blood collector is also an aggravating individual to deal with when buying or selling a machine. Everything they have for sale is listed above NIB pricing and they’re quick to point out that they’ve managed to shoved three aisles of Toys R Us products under the playfield, all the superbright purple LEDs they’ve put in the GI, their wicked cool topper, and that the game has less than 300 plays. Heck, less than 100 plays is common. But when you’re listing your well cared for machine, they want extreme close ups of the shooter lane, because if there’s an even tiny mark, it’s hard pass for them (or they want to knock like $1000 of asking price).
To put it clearly, the new blood collector tends to be a know nothing know-it-all with a loud voice. Sure, they have money, but they’re miserable to be around. They put some shine into the hobby with their money infusion, but they trample over so much in that process."

Quoted from jar155:

They negatively impact the hobby as a whole. A lot of fantastic people have gone quiet in the hobby, because they simply can't deal with the new bloods. Stern Pinball is going more and more vanilla with their designs, because design is now secondary to theme. Code has suffered, because code is now secondary to LE trims. We've seen a true gentrification in our hobby, and it sucks.
On the local levels, there is still a lot of greatness in the hobby, but online, it's quite often a trash fire.
Things will correct over time. I really don't worry about the long-term health of the hobby from a player's perspective, but I do think collecting will see a bit of an upheaval when the flash-in-the-pan big spenders get bored or move on.
We need more people who like to play. People who collect simply to have/own/showcase are creating a hollow foundation for the pinball market. We're seeing stuff crumble a bit right now. I don' think the bottom will outright fall out, but a readjustment of sorts is on its way.
Edit: I should probably clarify that to me that the pinball hobby =/= the pinball industry.

Quoted from Atari_Daze:

ebay.com link
^^^ this LOL
Sorry if someone already shared that, I'm just getting into this thread