Price & Stock Watch — Competitor Change Detection

Monitor a known list of competitor product URLs and get structured price-change and stock-change events, ready for your spreadsheet or automation workflow.

For ecommerce buyers, category managers and agencies that already know which products matter and need a small, auditable monitor.

Try the demo

{"demoMode": true}

The fictional demo shows a backpack dropping from $79 to $59 and coming back into stock, plus an inaccessible page that is marked unverified and not billed. Demo mode makes no web requests.

For real pages, replace the placeholders:

{
  "products": [{
    "url": "https://competitor-store.example/products/backpack",
    "sku": "BAG-BLUE"
  }],
  "maxItems": 100,
  "priceChangeThresholdPercent": 2
}

sku is optional when there is one unambiguous Product/Offer in the page's server-rendered JSON-LD. It is required to select among different product variants. The .example URL is fictional.

What it does

• Extracts title, SKU, decimal price, explicit currency, stock and the offer URL.
• Compares against the previous successful observation.
• Returns price_drop, price_increase, restocked, availability_changed and currency_changed events, with old/new values and price deltas.
• Applies the percentage threshold only to price changes; stock events still pass.
• Keeps failed checks from erasing the baseline or creating false stock alerts.
• Exports the dataset plus SUMMARY, SNAPSHOT, REPORT and formula-safe CSV.

Save a baseline

First run: supply product URLs. Second run: paste its SNAPSHOT into previousSnapshot. For scheduled operation, use an existing stateStoreId you own plus a unique monitorId and grant this Actor access to that storage. Schedule runs so the same monitor never overlaps. Snapshot storage is capped at the most recent 5,000 observations. For separate customers, use separate stores.

You receive change data in the output, not an automatic email. An Apify, n8n or Make workflow can route the dataset into notifications or your reporting system. Third-party integrations are configured separately.

Pricing

Proposed launch price: $3 per 1,000 verified product checks ($0.003 each), including normal runtime costs. No monthly rental and no startup fee. Event: product-checked; activate it in Apify Publication before selling.

Both the first baseline and unchanged successful checks are billed because the page was checked. Duplicate URL/SKU inputs are charged once per run. Blocks, failed requests, missing products and ambiguous offers have no Actor event fee. A product with a reliable price but unknown availability is billable and carries an explicit stock warning.

100 products checked once daily for 30 days cost $9 in Actor event fees. Each competitor URL counts separately: 100 products across 3 competitor URLs, daily for 30 days, means 9,000 checks and $27. Set a maximum charge per run.

What it does not claim

This is not automatic product matching, a universal retailer scraper or a pricing dashboard. It needs accessible product pages with an unambiguous server-rendered JSON-LD Product/Offer. It does not infer price from page text, execute JavaScript, convert currencies, bypass bot protection, or alter your shop prices.

Multiple offers, missing currency or ambiguous variants are reported as unverified. Currency changes are not mislabeled as price cuts. Unknown stock is not interpreted as out of stock. Small successive price changes are compared with the last check, not accumulated until they reach the threshold.

Maximum 1,000 URL/SKU checks per run; 2 MB per response after decompression; 10-minute crawl ceiling, bounded redirects/retries and robots.txt compliance. Only public HTTP(S) ports 80/443; no proxies or external AI charges.

Account plans, external workflow services and dataset access after completion may carry separate charges. Offline demos have no Actor event fees, although Apify runtime usage can still apply. Confirm your target pages work before scheduling.