Demand and availability: when the market moves the price

Used value also depends on how many people want a product and how many examples are available.

A common model is not necessarily undesirable, but buyers may have many alternatives and therefore more choice. Conversely, a sought-after product that rarely appears for sale can sustain stronger prices than technically similar gear.

Look not only at how much listings cost, but also at how many exist and how quickly the market changes. Many identical listings sitting unsold can point to excess supply or over-optimistic pricing.

Rarity and demand must be considered together: rare does not automatically mean valuable if very few people actually want the item.