Extract subscription receipts with AI and flag cost increases using a rolling three-invoice baseline
An easybits author describes two n8n workflows for a content business: seed a receipt ledger, then use AI extraction and deterministic arithmetic to flag subscription cost increases.
Evidence: The author reports this. We have not checked it beyond reading the source.
The business problem
A content shop's AI and design subscriptions were becoming more expensive without timely notice.
What was tried
Label two or three historical receipts per vendor in Gmail and extract vendor, amount, plan, period and date into Sheets. Label new receipts separately. Extract their fields with easybits, prioritising email-body values over attachment values. JavaScript compares each amount with the average of up to three prior receipts. Email an alert on increases; otherwise log silently. Append every receipt to advance the baseline.
What was reported (not reported)
The author reports building the system for a colleague. Actual savings and extraction accuracy are not reported.
Limitations
Promotes the author's extraction product. A larger receipt is not necessarily a price rise: plan and billing-period changes need review. Linked repository access failed during research; its code was not inspected.
What you need
n8n, labelled Gmail receipts, Google Sheets and an easybits extraction pipeline.
Sources
- u/easybits_ai (Felix), promoting easybits, on r/n8n ↗ Vendor case study, publication date unknown
Source published: unknown. Last reviewed here: October 19, 2026. Spot a mistake? Tell us.
Tools in this workflow
- Google Sheets: Stores the rolling ledgerTry Google Sheets
- n8n: Runs receipt workflowsTry n8n
- Gmail: Holds labelled receiptsTry Gmail
- easybits: Extracts receipt fieldsTry easybits
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