This is a synthetic practice exercise for a bank-reconciliation article. Use only bank-export.csv, cash-ledger.csv and supporting-evidence.csv in this new project. All evidence notes are invented practice evidence.

Reconcile DEMO-OPERATING in USD for 1–30 September 2026, using evidence available by 5 October. Source controls: bank opening $10,000, bank closing $9,548; books opening $10,000, books closing $10,200. No prior outstanding items. Signed amounts are cash into the company account positive and cash out negative.

First verify each source independently and identify any repeated bank transaction identifier before accepting rows. Preserve duplicate/excluded source IDs. Bank row IDs and ledger row IDs are unrelated: equal numbers, amounts or nearby dates alone do not prove a match. Confirm one-to-one matches using payment/invoice references and the supporting notes. Do not consume a bank or ledger row twice. Separate candidates, supported matches, timing differences, entries missing in books and unexplained items. Preserve ambiguous equal-amount cases and explain what evidence resolves or fails to resolve them.

Build an inspectable reconciliation review/report with: source controls, a supported-match register with both row IDs and reasons, unmatched rows in BOTH directions, signed bank-side and book-side adjustment bridges, and the remaining difference. Keep unexplained amounts open; do not invent a balancing entry or post anything. Save the resulting tables and a downloadable review file. Include a clear summary view suitable for a reviewer, with source rows and calculations available. Ask only if a needed business rule is genuinely missing.