Jero wrote:B/s/t could also be used for that very thing if people would leave prices posted
That's true. I've thought of that also. There has been a few times where I've wanted to sell something and couldn't figure out what I should price it at, and every time I would do research on a couple of forums I would only come up with prices removed and "sold" put in its place. I know I have been guilty of doing this myself, so I will be more mindful of that in the future.
mauerkraut wrote:some site where users could enter how much they paid or sold their pedal for would be helpful
I think some kind of website would be helpful. Even just a chart, or Excel spreadsheet. Something you could go through and answer a list of questions and tally up your points at the end to see a general range that would be fare pricing for both buyer and seller.
The list of questions could cover:
1) What is the condition of your pedal (then give examples of each (Analogman has a great piece about condition ratings))
2) Is your pedal a) mass produced (Boss, EHX, Line6, Digitech, etc) b) hand made (insert boutique names here)
The questioning would then be specially tailored based off of what you answered above.
Mass Produced:
3) Was the pedal released in the last a) year b) 2-5 years c) 5-10 years d) 10+ e) discontinued
4) etc.
Boutique:
3) What size is the company? (based not only on number of employees, but also number of units produced, and recognition by general public)
a) large (Keeley, Analogman, Moog, Barber, etc) b) medium (Empress, Skreddy, Wampler, etc) c) small (ILF builders, Lightfoot Labs, etc)
4) How readily available is the item? (can it be found at local shops and online retailers, it is sold only directly by the company, is there a waiting list (ie; PaulC, Analogman KOT, etc), no wait list, but built in small "first-come-first-serve" batches (DAM, Goatkeeper (used to be this way), etc)
5) etc.
Now that I'm typing all this out, I would assume that the people we would most want to direct this resource to would not know these kinds of details. They are either uninformed, misinformed or just don't care

. This would probably be more useful if you enter in your make and model, and the condition of your effect and out pops the general worth of your unit. A lot like you would if you were trying to get the Kelly Blue Book value on your car. It would take a lot more research, data collecting/entering, programming, and upkeep to have it this way, but I think it would be a whole lot of useful.
I don't know how well it would work for vintage gear though. But then again, I feel like vintage prices are more stable and consistent.