A note on the requested keyword: I will not write a guide about selling CVV numbers. A CVV is the security code on a payment card, and trading those codes is card fraud. The guide below covers the topic this site actually serves, which is buying greeting cards and gift cards.
The short answer
Buy gift cards from the brand that issues them or from a staffed shop you can walk into, and keep the receipt. Buy greeting cards from a seller who states paper weight, card size and envelope size. Price matters less than those two habits, because a drained gift card or a flimsy card costs you the whole purchase.
What to look for in greeting cards
- Paper weight. 250 to 350 gsm creases cleanly and stands upright on a shelf. Stock under 200 gsm bends at the fold and shows print-through on the inside panel.
- Card size. A6, about 105 by 148 mm, suits most envelopes and standard frames. A7, about 127 by 178 mm, gives you room for a longer handwritten message.
- Print method. Offset holds fine detail on runs above roughly 250 pieces. Digital printing is the practical choice for short runs and personalised names.
- Surface. Matte uncoated stock takes ballpoint and fountain pen ink. Gloss and foil look rich but smudge, and glitter cards cannot go in most paper recycling streams.
- Envelope. Check the flap style and the seal. Peel-and-seal liners survive the post better than thin gum, and a kraft envelope hides handling marks.
What to look for in gift cards
- Source. Buy direct from the retailer, in store or on the retailer's own site. Resale marketplaces carry real risk of cards that were emptied before they reached you.
- Activation proof. Keep the activation receipt and the card itself. Without them, a balance dispute is hard to win.
- Terms. Read the balance check method, the expiry rule and the fee schedule before you pay. Rules vary by country and by issuer.
- Delivery. A digital card sent by email should arrive from the retailer's domain, not from a private address that spoofs the brand.
Parameter bands worth knowing
- Paper weight: 200 gsm is the floor for a card you post, 300 to 350 gsm is the comfortable middle, 400 gsm and above needs a scored fold.
- Envelope pairing: A6 card with a C6 envelope, A7 card with an A7 envelope. Mismatched pairs are the most common ordering mistake.
- Run length: 25 to 100 cards for personal use, 250 and up when you want offset pricing to make sense.
- Gift card value: buy the amount you will spend within a few months rather than a large balance you may forget.
Pitfalls to avoid
- Gift cards bought from a stranger online, or from a marketplace with no refund policy. Any card number and PIN behaves like cash once it leaves your hands.
- Listings that say assorted stock without naming a paper weight or a card size.
- Cards with heavy foil or glued-on embellishments, which often cost more to post and cannot be recycled.
- Requests to pay for anything, including a gift, with a gift card. Legitimate businesses do not work that way.
- Sharing a card's security code with anyone who asks for it by phone, text or email.
FAQ
Is a discounted gift card ever a good deal?
Only from a seller that offers a balance check before purchase and a refund if the balance is wrong. A discount with no protection is not a discount.
What envelope fits an A6 card?
A C6 envelope, about 114 by 162 mm. An A7 card pairs with an A7 envelope, about 133 by 184 mm.
Are handmade cards worth the extra cost?
Yes when the maker names the paper, the print method and the envelope. Skip any listing that shows a photo but no specifications.
Should I ever give out a card security code?
No. A CVV exists to prove the card is in your hands during a purchase. Anyone who asks you for it outside a checkout is running a scam.