When you scan the barcode with your phone's camera, it will tell you that they don't want it, it doesn't recognize the barcode, or what they will buy it from you for.
What an amazing app @getonthetrain. I love that feature in particular.
Sadly they don't seem to have a UK branch but when I investigated further it seems that they themselves are the US branch of a UK company musicmagpie.co.uk. I'll have a bit more of a look when I have time. 😊
I look forward to hearing how you do with your next haul. 😊