What the link does
TheBigBois, which describes itself as an official Packs.com partner, says its /r/ link pre-attaches its code, and the 5% is added when you top up. Creators run the same setup under their own names, which is how our link works too.
We haven't seen the 5% stated on Packs.com's own pages. Treat it as a partner's description and confirm it on your first deposit.
Coins are not cash
Selling a card back pays Coins at the estimated resale value shown at reveal, per Packs.com's terms. PackRipper reports Coins can't be withdrawn as cash, so value only leaves the site in the cards you ship.
Purchases are final, and Packs.com's refund policy estimates 2 to 4 weeks for shipping.