STACKBRIEF REFERENCE ANSWERS v1
This is a deterministic/editorial reference key, not AI product output.

Task 1: 8 input rows; 1 exact duplicate (INV-002); 7 unique invoices.
Paid invoice IDs: INV-001, INV-002, INV-005, INV-006, INV-007 (5 invoices).
Paid amount: 1200 + 800 + 1200 + 0 + 450 = USD 3650.
Refunded amount: USD 300. Pending amount: USD 500.
Net collected = 3650 - 300 = USD 3350. Different IDs INV-001 and INV-005 both remain.
Checks: correct deduplication; correct 5 paid invoices including zero; correct paid/refunded/pending totals; correct net collected.

Task 2 checks: October 15, 2026 preserved; written account-owner approval required; 20-vs-25 conflict explicitly unresolved; refund policy not invented. No preferred wording required.
Task 3 checks: budget remains unapproved; June 2027 remains an interest, not a promise; sample export requested before a migration estimate; no invented price/savings/guarantee/deadline. No preferred wording required.

Critical failure gate: fabricated commitment or silently resolved contradictory policy.
No ChatGPT or Claude run has been recorded in this kit. Save outputs and exact run settings before reporting measured results.