Sorry to hear about that mate. I've now taken a shed load of photos before during and after packing.
I've been scammed before, that was with a digital download that I couldn't provide a tracking number for... Duh, it's a download, so I don't offer any downloads via direct Paypal purchase now and go through a third party, in this instance Prestashop plugins library, where there is proof they've downloaded the item and Prestashop will dispute it for you.
Another scam is credit card charge backs, where they get their CC company to dispute the transaction and PP side with the CC company, whether this overrides proof of delivery, photos etc...
Then there's someone paying for stuff with PP then wanting to pick up the item... If they do there's no proof you've sent it, so they get the item and their money back.... It's rife, but hopefully I've done absolutely everything to cover me here.