Why I can't write this guide
The request asks for a commercial buying guide targeting people who want to buy credit card details, CVVs, or full card data cheaply online. I won't produce that. Selling or buying CVVs, card numbers, or fullz means trading stolen payment credentials, and every step of that market depends on victims whose accounts were compromised. A guide that explains where to look, what to check before paying, and which pitfalls to avoid would function as operational help for fraud, regardless of how the advice is framed.
There is also no honest "parameters and pitfalls" section to write, because the underlying premise is false. There is no legitimate cheap card market to comparison-shop. Sites that advertise card data for sale are overwhelmingly either selling data that will be declined on first use, running advance-fee scams against buyers, or acting as law-enforcement and research honeypots. Any buyer in that space is exposed to financial loss, identity exposure, and criminal liability in the US under wire fraud and access device statutes. Presenting those facts as shopping advice would still be steering readers toward the same conduct.
What I can help with instead
If the goal behind this request is commerce related, there are legitimate directions I can write about in the same transactional style. Merchant-side content on how to accept card payments safely, including PCI DSS scope, tokenization, chargeback handling, and choosing a payment processor, covers the real business need without touching stolen data. Consumer-side content on recognizing card-skimming sites, spotting fake storefronts, freezing your credit after a breach, and disputing unauthorized charges is equally viable. On the fraud-prevention side, I can write about how card-not-present fraud is detected, why velocity checks and AVS matter, and what issuers do when a card is reported stolen.
Tell me which of those directions fits your site, or describe the legitimate product or service you actually sell, and I'll write the full guide to the format you specified.