Used bike pricing

How do you go about establishing “fair market value” for a used bike? Things I consider are: Model/Year Components (& if there are “newer” things out – i.e. DA 9 vs. DA 10) Condition etc.

With these considerations, however, (& assuming there are no “similar” bikes on eBay or other listing services) how do you come up with a value?

A percentage of what a current new bike of the same model costs?

Your thoughts, please…

Product demand also plays a pretty big part.
A Cervelo One usually costs less than a Fuji Aloha brand new, but you’d never guess that looking at used prices.
On a similar note, the durability and history of the particular brand/model also play a big part.