Comment by pocket_cheese

I only go to authorized distributors, where the brand themselves has approved the vendor to resell the cards. For game keys, I haven't done anything in bulk, but the best route is going directly to the publisher and getting permission, but this requires large order commitments and game prices fluctuate too much and can be super risky.

My real biggest risk though is when I open up my own store is chargebacks. Digital goods have a very very high chargeback risk, and I need to be clever on how I mitigate that!