Country, geography and shipping costs
A price observed abroad does not automatically transfer to the market where you are buying or selling.
Differences in VAT or taxes, import costs, currency, shipping, insurance and local availability can make two markets only partially comparable.
For bulky or fragile items – such as cabinets, heavy digital pianos or large mixers – the realistic buyer pool may be mostly local. For a small pedal that is easy to ship, the market can be much wider.
Use foreign prices as evidence, but always bring the comparison back to the economics of the actual transaction.