C'mon guys....its VERY SIMPLE ECONOMICS....supply and demand....its truly that easy. AxeFX and Cameron hold their value...no sheet...try and go buy one...they are both back ordered....up until what...a week ago you couldnt even get a cameron unless you got someone willing to part with theirs. All these boutique builders listed that value is really starting to take a hit...(Bogner, Wizard, Deizel, and the list goes on...) 5 years ago there were a relatively small number of them available...but as the years go by more and more are being built and new builders are popping up as the "Flavor of the Month" so the older amps are no longer as desirable and more are available...so in order to sell your used one you either have to make it more desirable by adding extra's, adding new tubes, or lowering the price in order to flip yours compared to the other 5 - 10 that are available right now by other guys who want to try new stuff.
I mean it really is just supply and demand. If you have something that someone cant readily get then its worth more. That simple. If you are selling something used and I can get it brand spanking new for say 300 - 500 more, then it doesnt make sense to buy used if I can get the warranty and know for fact it hasnt been beat to hell and back.
Take my rack mount SLO....there arent many built, they arent being built anymore, and you probably see what...3 - 5 a year come up for sale total...and most of those arent in what I would call excellent condition....so I could probably sell mine at quite a premium....kinda makes sense, since I am one of only 4 guys that will sell one this year...when buyers outnumber sellers it costs more...duh....
Also, when the model you have is constantly being updated, then the older model usually takes a significant hit!! Look at the XTC...the original 101b...I have seen them go for 1700 - 1800 dollars....compared to the classic which is more, then the 20th which is way more... Look at Splawns...grab an original QuickRod that has no gear knob...man those are like less than half price of what they were new just 5 -6 years ago...that is unless some internet whiz kid suddenly says the older ones are better...then watch out!! they will triple in price!! LOLOLOL