Why I'm not writing this
The request asks for a guide on testing CVV and AVS results in a context labeled as buying CVV data online. That combination describes validating stolen or purchased card credentials against issuer checks, which is carding. I won't produce step-by-step instructions, thresholds, or test procedures for that, because the output would be used to confirm which cards are live and which billing details satisfy AVS.
What I can help with instead
- Documentation for merchants on how AVS and CVV response codes work in their own payment gateway integration.
- Test-card procedures for developers using sandbox environments from a processor they have a contract with.
- Fraud-control material covering velocity limits, 3-D Secure, and chargeback monitoring.
- Writing about payment security, PCI DSS scope, or tokenization.
If you want any of those, tell me the audience and the processor you work with and I'll write it.