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How I Built an Amazon Price Drop Alert System for $3/Month (No Code Required)

I sell on Amazon FBA. Watching competitor prices is literally my job.

For 8 months I did it manually. Every morning: open 50+ product pages, compare to yesterday, log changes in a spreadsheet.

Then I automated it. Now I get Telegram alerts when any tracked product changes price. Total ongoing cost: $3/month.

Here's the exact setup.

The Problem: Manual Price Monitoring Is Killing Your Margins

If you don't know when competitors drop prices:

  • You miss the window to match and win the Buy Box
  • You lose sales for 6-12 hours before you even notice
  • You can't identify pricing patterns (flash sales, weekend dips)

Price monitoring services like Keepa charge $19/month just for Amazon data. And you still have to build your own alerts.

The Stack I Use

  • Apify Amazon Scraper — extracts price, seller, stock, rating for any ASIN
  • n8n (self-hosted, free) — orchestrates the workflow
  • Telegram Bot — instant alerts to your phone

Total infra cost: ~$3/month in Apify compute credits.

Step 1: Set Up the Apify Amazon Actor

The Amazon scraper actor accepts:

  • Product URLs or ASINs
  • Search queries ("bluetooth headphones under $50")
  • Category IDs

It returns:

{
  "asin": "B0EXAMPLE",
  "title": "Product Name",
  "price": 29.99,
  "originalPrice": 34.99,
  "seller": "Brand Direct",
  "rating": 4.3,
  "reviewCount": 2847,
  "inStock": true
}
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Run it on a schedule (every 4 hours for active monitoring, daily for background tracking).

Step 2: Store Baseline Prices

First run = baseline. Store in a simple Google Sheet or Airtable:

ASIN Product Baseline Price Date
B0ABC123 Competitor Widget $34.99 2026-01-15

n8n Google Sheets integration handles this in 3 nodes.

Step 3: The Alert Logic

// n8n Function node
const currentPrice = $input.item.json.price;
const baselinePrice = $input.item.json.baselinePrice;
const dropPercent = ((baselinePrice - currentPrice) / baselinePrice) * 100;

if (dropPercent >= 15) {
  return {
    alert: true,
    message: `⚠️ ${$input.item.json.title}: dropped ${dropPercent.toFixed(1)}% ($${baselinePrice} → $${currentPrice})`
  };
}
return { alert: false };
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Alert triggers at 15% drop. You can tune this.

Step 4: Telegram Notification

n8n has a Telegram node. Connect your bot, set chat_id, done.

The alert looks like:

⚠️ PRICE DROP ALERT
Product: Competitor Bluetooth Speaker
ASIN: B0ABC123
Change: $34.99 → $27.99 (-20%)
Link: amazon.com/dp/B0ABC123
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Arrives on your phone within 5 minutes of the price change.

My Actual Numbers

I track 500 ASINs across 3 categories.

Apify runs 500 results × $0.002/result = $1.00 per run
Running 3x daily = $3/day... wait no

Let me recalculate:

  • 500 ASINs × $0.002 = $1.00 per run
  • 3 runs/day × 30 days = $90/month

That's for aggressive monitoring. For daily monitoring:

  • 1 run/day × 30 days = $30/month

For a focused 100-product watchlist:

  • 100 × $0.002 × 30 = $6/month

Still way cheaper than Keepa Pro at $19/month.

Bonus: Competitor New Product Detection

The same actor works for competitor store monitoring:

URL: amazon.com/s?i=merchant-items&me=SELLER_ID&rh=p_4%3ABRAND
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When a new ASIN appears in results that wasn't there yesterday → instant alert.

I get competitor new product launches before they show up in ads. Huge advantage for adjusting your own listings.

The Bundle

This Amazon price monitoring is one of 30+ workflows I've packaged.

Apify Scrapers Bundle — €29

Includes the Amazon actor configuration, the n8n workflow JSON, and the alert logic — ready to import and run. You'd spend 4-6 hours building this from scratch. For €29 you can run it today.

Also includes:

  • LinkedIn lead scraper config
  • Google SERP rank tracker
  • TikTok product trend monitor
  • Instagram brand mention tracker
  • And 25 more actor setups

One-time purchase. All updates included.


Running FBA or selling on Amazon? What's your current price monitoring setup? Drop a comment — always comparing notes with other sellers.

n8n AI Automation Pack ($39) — 5 production-ready workflows

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