▸case-12 When a SaaS customer downgrades from a $1,200 annual plan to a $100 monthly plan halfway through the year, the billing pipeline currently discards the remaining balance. How should unused funds be handled during plan downgrades? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-13 For annual recurring subscriptions, a growth team suggests charging the user's card on file on day 365 without prior notice. What automated billing communication requirement should be implemented before processing annual renewals? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-22 A tax-exempt non-profit enterprise organization provides a validated tax exemption certificate. The default invoice generator continues to add state sales tax to their recurring monthly bill. How should the tax engine handle this account? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-01 We need to issue a one-off manual invoice to an enterprise partner for an ad-hoc sponsorship payment of $50,000. We do not use subscription software or automated billing flows for this client. How should engineering issue and track this single manual billing transaction? | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-19 A storage product charges $20 for up to 100 GB, and $0.50 per GB for usage over 100 GB. A developer wrote logic that charges $0.50/GB for all 105 GB once usage exceeds 100 GB. How should tiered overage billing be calculated? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-03 An accounting audit identified a $120 manual discrepancy in last month's general ledger revenue account due to a bank wire transfer fee. The subscription billing platform was already accurate. How should accounting book this single manual journal entry? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-11 The engineering team finished building regional VAT and sales tax calculation logic and plans to switch on live production billing immediately. What compliance step must be completed before launching in production? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-14 After running automated recurring billing for a month, finance notices that payment gateway bank payouts do not match software revenue totals because fees and refunds were omitted. How should the billing pipeline perform reconciliation? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-04 Design the state machine transitions for a monthly recurring subscription when a payment attempt fails. A team member suggests immediately marking the subscription as canceled upon the first charge failure to stop service access. Outline the standard state sequence to implement instead. | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-06 When an automated recurring payment fails, a junior developer configured the system to re-charge the customer's payment method every 2 hours continuously until successful. What retry strategy should be implemented for failed payment dunning? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-23 A merchant issues a $100 partial refund on a $500 subscription invoice that originally included $40 in regional tax. The payment system currently refunds $100 while keeping the entire original tax liability recorded. How should tax be adjusted on partial refunds? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-02 Our company uses a legacy third-party billing vendor where pricing tiers, billing cycles, and payment retry logic are completely locked by contract and cannot be reconfigured. We need to write customer support instructions explaining how buyers can view their static receipt in the portal. How should support explain receipt viewing without altering billing flows? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-08 To test a new dunning recovery flow on the staging server, a QA engineer configured the payment gateway integration with live production API keys and executed $0.01 micro-charges against real credit cards. What testing safety rule must be enforced? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-09 An API service platform charges customers based on request counts processed each month. An engineer suggests triggering a payment gateway charge immediately for every individual API call. How should usage-based billing be architected? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-21 A subscriber whose account is in past_due status following two payment failures updates their payment details in the billing portal. What actions should the subscription billing system execute upon receiving the updated payment method? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-05 A customer paying $100 per month upgrades to a $300 per month tier exactly 15 days into their 30-day billing cycle. The developer wants to charge the full $300 immediately without crediting unused time from the prior tier. How should the proration engine structure this mid-cycle charge? | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-10 We need complete implementation patterns, edge-case validation checklists, and multi-currency billing examples. Where in the repository's resource files should developers look for detailed execution guidance? | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-20 Before deploying automated proration code to production, QA ran sandbox payment test cases and verified that simulated payment calls returned standard success codes. What financial verification step must be performed before signing off? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-17 A platform bills international clients in EUR and GBP. A developer proposes converting invoice amounts using live dynamic spot rates at the exact millisecond of every invoice view request without recording exchange rates at billing time. How should multi-currency invoicing handle rates? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-07 Our SaaS application sells globally to consumers and B2B clients across the EU and the US. The initial software design applies a flat 8% sales tax to every invoice worldwide. How should regional tax calculation be structured in the automated billing engine? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-18 A subscription completed its full dunning retry schedule over 30 days without successfully collecting payment. The system currently leaves the subscription in past_due status permanently. What state transition and accounting treatment should take place? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-15 To minimize involuntary customer churn caused by expired payment cards, what automated background task should be added to the subscription management engine? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-16 When a customer's card charge fails during subscription renewal, an engineer proposes immediately revoking feature access while retries are scheduled over the next week. What access policy should be maintained during dunning? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |