Unified payment processing for multiple accounts under the same corporate entity is achieved through consolidated billing, a feature of AWS Organizations. This allows for a single bill and better tracking of overall spending, potentially unlocking volume discounts due to combined usage. An AWS Support Plan is focused on the level of support received and does not deal with invoice consolidation. The AWS Pricing Calculator helps estimate costs but does not handle actual billing. AWS Shield is a managed Distributed Denial of Service (DDoS) protection service, unrelated to billing or account management.