For higher value goods people usually prefer others, I think Backmarket.com is one of the main ones (it's definitely the main option for electronics in France)

For higher value goods people usually prefer others, I think Backmarket.com is one of the main ones (it's definitely the main option for electronics in France) but there's also Refurbed (know it from Belgium but I think it's German) or Rebuy (know it from the Netherlands but it's German as well) for example. Each of those three claims to be the largest one in some metric.