Workflow Automation Builder (Zapier/Make/n8n)

Automate this workflow: "{{manual process description}}" using {{Zapier/Make/ n8n}}. Specify: 1) trigger (app + exact event + filters to avoid false runs); 2) step-by-step flow with each action app, field mapping, and data transformations needed (formatter/parser/date math); 3) lookup/update logic (dedupe key — search then create/update, never blind create); 4) error paths: missing fields, duplicates, API failure, notification on failure; 5) idempotency (what happens if the zap runs twice); 6) test record instructions; 7) rate limits/cost estimate; 8) human approval step recommendation for risky actions (sending external email, refunds). Provide the flow as a numbered spec ready to build, plus the 3 edge cases likely to break it.