If you're selling digital codes and you want protection, ship a copy/photocopy of the code to the buyer via USPS Fist Class mail with delivery confirmation. Build the shipping costs into the item price. It's the only way you'll have protection from INR and Unauthorized Chargeback disputes because at that point you can show proof of delivery.
As with any sale, your protection against NAD disputes/chargebacks is very limited.
My understanding though was that eBay made it so sellers could not sell digital / non-tangible items unless in the classifieds sections. Rules like this change all the time but regardless, how are your metrics not getting hammered in the "uploaded tracking" section?
