The fact people are willing to give people $800+ to complete strangers for an item you have no financial protection for in case you get scammed or robbed is wild to me. I’d just either buy new or used from an actual retailer.
Hell, even eBay has money back guarantees.
eBay is probably the safest place other than Apple themselves because of the money back guarantee and it being super pro customer.
It’s Facebook marketplace and the local meetup sales you have to worry abut more because it’s all cash and you have no way to get your money back.