This is very dodgy. I sent my phone off to a company who offered to buy it online.
They then received it, halved their offer
and sent an email with their terms and conditions on it after they received the phone stating I needed to pay £10 fee before they would send it back to me.
It's clearly very sharp practise and they're now refusing to send it back.
What would you do ? I'm thinking trading standards? Doing a small claims thing?