I ordered many times to buy on mercari jp, it's quite good never had an big issue and payments are always made instantly, but they often take more than 3 days to consolidate packages which can be frustrating when you're in a hurry, and it's pointless to contact support to have any human contact because they will follow their guidelines without taking your specific issue in consideration, finally i find their optional fees kinda expensive at the end, if you want to be really sure about an item you have to pay 500yen for inspection + ask a photo at 300yen.
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