This doesn't prevent a chargeback from paypal when the buyer claims he received an empty box. Paypal sides with the buyer 99% of the time, proof or not.
Agreed.
While many members here have had good experiences so far via Swappa, unfortunately I'd say it's only a matter of time until the fraudsters ruin it the same way they have with eBay.
PayPal chargeback fraud just seem way to easy to get away with as a buyer. Most sellers aren't expecting it, and even if you document everything properly you can see countless examples online of PayPal siding with the buyer.
While it's not as easy as selling online and you don't have as many potential customers, meeting at a very public place via CL and doing a cash only transaction is usually the 'safest' way (provided you don't get robbed) to sell a phone.