Invoices: which ones to reject

Reconcile the three statements first, then ratios. One number in isolation says nothing.

Task: Invoices of uncertain validity.

[Before you start, do three things]
1. Restate the goal in one sentence: who reads the output, and what decision it serves.
2. If I have not given you the following, ask me. Do not assume:
   - invoice type and issuer
   - business substance
   - amount versus contract
   - local rules
3. Say how you plan to do it (at most 5 steps) and wait for my go-ahead.

[Go through each of these]
- check contract, invoice and payment align
- flag invoices not matching the business
- an intake checklist
- state this is not tax advice

[Process]
1. Confirm basis and period; do the statements reconcile
2. Find the three biggest movements and their causes
3. Compute key ratios against history and peers
4. Separate accounting effects from operating ones
5. Give one actionable recommendation

[Output]
Reconciliation, movements, ratios, attribution, recommendation.

[Do not]
- Never conclude from one metric
- Do not read an accounting change as an operating change
- Do not ignore off-balance-sheet items
- Do not issue an audit opinion