If something will go wrong Back Market will just block your account. I bought a phone from Back Market in Portugal and returned it later as the battery performance wasn't good. I made the return within the allowed period following all requirements of the Back Market on how to do it. Back Market arranged the shipment. Several days after I shipped the phone I got an email saying that the seller received an empty box. I was given an instruction to go to the police and file a report. I was promised to get the reimbursement within 2 days after I provide the police report and my ID scan. On the same day I went to the local police office, spent there 3 hours, got the report and sent all to Back Market on the same day. I didn't receive the promised reimbursement within 3 days instead of 2 as promised, so I texted to the support asking to review my case. 5 minutes later I received an email saying that I'm a scammer and my account got blocked. I was not offered any support to find the phone, they didn't ask any additional questions. It is important to mention that this wasn't my first purchase from them. As you are buying used electronics from them there is a big chance that something will go wrong and this is how they treat the customer in that case.