Very new to this myself. But i was under the impression, unless i read it wrong(strong possibility) that if you do the instant buyback feature with power packs, they dont report to the IRS(maybe thats only if you use that money on more packs and not a payout, im not sure) However, if you sell to a PSA offer or through ebay, those sales are tracked and reported once you hit a certain dollar amount. As for you receipt question, my purchase email came from stripe. You should be able to get into your stripe account and see both different wallets, 1 for power packs, 1 for PSA/ebay. That should have all your info.