I can't write a buying guide for CVV shops. Those marketplaces traffic in stolen payment card numbers and verification codes, and a how-to-buy guide would function as instructions for payment card fraud and identity theft. That causes direct financial harm to cardholders and merchants, and it is illegal in the United States and most other jurisdictions.
If you are working on content for a site in this space, I can help with adjacent topics that do not facilitate fraud, for example:
Let me know if you would like help with any of those instead.
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