First to blame is your primary school English teacher 
But seriously, yes many collectors find it very frustrating. It starts with the dealers inflating the prices and keeping them there for prolonged periods of time. Casual observers have an inherent trust with a dealer thinking the prices they are seeing is the cost of true value and service of this new interest they have. Sadly, they later find out when it comes to pinball, not all dealers offer the best service, sales and advice. The advertising method of overpricing a machine has had an impact on what people are wanting for their personal machines during sale time. Space Invaders for close to 6k - and my personal favourite a Stern Lightning which a couple of years back failed to sell for 2.2k and was repeatedly listed by the dealer for literally 18 months (was a running joke alongside the Granny and Gators) - now the same seller has another unit of the Lightning for over 4K! Who can forget the recent Teed Off for what was it? 7K?The seller didn't even bother putting the translite in for the photo. Almost criminal offence! All props if these machines are fetching the asking prices but many are not and it does confuse the market.
Even collectors on other forums will congratulate a high 3k asking price of a machine for sale when the same title was a 2k machine every day of the week only so long ago! A well restored/reconditioned machine will always command interest and a higher dollar - it would be particularly frustrating if you had one of these for sale and others come along without the work done asking for around the same amount.
It really is an interesting time for the pin market. If this proposed economy downturn comes, they say the first thing to go out the window are luxury items.
What happened? Didn't mind taking the piss with me and my grammar. But when your own mistake gets pointed out on the post you have a crack at me about you edit it. If you spell lightning with an e you got to cop it sweet.
