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AutomationOctober 13, 20264 min read

Cafe Supplier Price Watch: Catch Coffee Price Jumps Before the Invoice

By , Founder, SkynetLabs

Coffee prices jump and you only find out on the invoice. See how an n8n workflow checks supplier prices weekly and alerts you with options when one spikes.

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Coffee prices jump and you find out on the invoice. By then the order has shipped, the menu is printed, and your margin on every flat white has quietly shrunk.

Our short video shows an n8n workflow that watches your supplier prices every week. Spike detected? You get an alert with options: renegotiate, switch, or adjust the menu. Never blindsided again.

Watch the 30-second walkthrough on our YouTube channel @Skynetlabs2k25.

Example, not a result. The weekly check and the three options in the video are an example. Choose thresholds that match your margins, such as flagging any rise above a set percentage.

Why do supplier price rises hurt small cafes?

Cafes run on thin margins, and ingredients such as coffee, milk and packaging move in price more often than menus do. A small rise on a high-volume item adds up over a month, and invoices often arrive after you have already served the stock.

Most owners track prices by memory or by scanning invoices when they have time. That means a rise is noticed late and acted on later. A weekly automatic check turns a surprise into a decision made with time on your side.

How does the price-watch workflow work?

The workflow compares this week's prices with a stored baseline and speaks up only when something moves.

StepWhat happensTool
1. Read current pricesEvery week n8n collects your supplier's latest prices from a price list page, a spreadsheet or emailed price sheets.Schedule + HTTP / email node
2. Compare with last timeEach item is checked against the stored price from the previous week and a longer baseline.Code / Sheets node
3. Flag a spikeAny item that rises more than your threshold is marked as a spike. Everything else stays quiet.IF node
4. Send an alert with optionsYou get a short message: the item, the old and new price, and a prompt to renegotiate, switch or adjust the menu.Email / chat node
5. Save the historyThe new prices are stored so you can see trends and prove a rise when you negotiate.Sheets / database node

The workflow does not decide for you. It makes sure you hear about a rise while there is still time to choose.

What you need to run it

  • An n8n instance
  • A source of supplier prices n8n can read, such as a web price list, a shared spreadsheet or regular price emails
  • A baseline list of the items you care about most
  • A threshold for what counts as a spike
  • An email or chat account for alerts

Start small. Track just the five or ten items that make up most of your spend, such as espresso beans, milk, oat milk and takeaway cups. A short list keeps the alert useful. Once you trust it, add more. Keep the history sheet too: when a supplier announces a rise, being able to show the last twelve weeks of prices makes the conversation about fairness rather than guesswork.

Honest limits

  • It can only watch prices that are available in a readable form. Prices given only by phone cannot be tracked.
  • Some supplier sites block automated checks or change layout, which means the workflow needs occasional maintenance.
  • It spots a rise but cannot negotiate or find a cheaper supplier for you.
  • Prices that include delivery or bundle discounts may need extra rules.
Hear about the rise this week, not on next month's invoice.

Frequently asked questions

How does n8n know the supplier's prices?

It reads them from wherever they are published: a web page, a spreadsheet the supplier shares, or emailed price lists. If the prices are not available digitally, the workflow cannot watch them.

How often should I check prices?

The video uses weekly as an example. Daily is rarely needed for a cafe, and weekly is usually enough to catch a trend.

Can it switch suppliers for me?

No. It alerts you and offers options. The decision, and any conversation with a supplier, stays with you.

Is it legal to check a supplier's website automatically?

Public price lists are generally fine to read, but check the supplier's terms. A friendlier route is to ask them to email you their price list.

Next step

Pick your five biggest ingredient costs and write down what you paid last month. That is the starting watch list. Ask for the price-watch workflow and we will build it around your suppliers.

To have us build it for you, get in touch through skynetjoe.com or hire SkynetLabs on Fiverr: https://www.fiverr.com/agencies/skynetjoellc.