Multi-Store Stock Alert: One Feed for Amazon, eBay and Shopify

Watch the same product across Amazon, eBay and any Shopify storefront in a single run. Every source comes back in one normalised shape, the cheapest place to buy right now is named, and you get an alert when your target price is met or something comes back in stock.

Built for buyers, resellers and sourcing teams who currently keep three tabs open and compare by eye.

How it works

flowchart TD
    A["Your product: ASINs,<br/>eBay terms, Shopify stores"] --> B["Amazon Price Tracker"]
    A --> C["eBay Price Tracker"]
    A --> D["Shopify Price Tracker"]
    B --> E["Normalise to one shape"]
    C --> E
    D --> E
    E --> F["Scope to the tracked product<br/>by title"]
    F --> G{"Compare"}
    G --> H["Cheapest source"]
    G --> I["Target price met"]
    G --> J["Back in stock"]

This Actor does no scraping itself. It chains the three source Actors, so each store is read by the Actor that specialises in it, and a store that fails does not take the run down: you still hear about Amazon on a morning when eBay is throwing challenges.

Built for

• Resellers and arbitrage buyers who need the cheapest source, not three tabs
• Procurement and sourcing benchmarking one part across marketplaces
• Collectors waiting for any store to hit a number
• Brand owners watching where their product is being sold and at what price

Input

{
  "productLabel": "insulated travel mug",
  "amazonAsins": ["B0FGJF172R", "B0FGJCYQKK"],
  "amazonMarketplace": "US",
  "ebayKeywords": ["zojirushi travel mug"],
  "ebaySite": "US",
  "titleMustContain": ["mug"],
  "targetPrice": 30
}

Setting	What it does
amazonAsins	ASINs to price. Leave empty to skip Amazon
ebayKeywords	eBay searches to run. Leave empty to skip eBay
shopifyStores	Shopify storefronts to read. Leave empty to skip Shopify
titleMustContain	Scopes every source to the product you are actually tracking
targetPrice	Alerts when any in-stock offer hits this price or lower
onlyAlerts	Return only drops, stock flips and new listings

Set titleMustContain whenever you include a Shopify store. A storefront returns its whole catalogue, and without a title scope the comparison will happily name an unrelated product as your cheapest offer.

Output

{
  "source": "ebay",
  "sourceLabel": "eBay",
  "group": "insulated travel mug",
  "key": "ebay:307065683170",
  "title": "Zojirushi SM-KHE48 Stainless Steel Travel Mug 16oz",
  "price": 26.23,
  "currency": "$",
  "inStock": true,
  "seller": "thriftbooks_us",
  "changeType": "new-listing",
  "isCheapest": true,
  "url": "https://www.ebay.com/itm/307065683170",
  "checkedAt": "2026-09-15T18:40:35.008Z"
}

The run summary names the winner and how each source fared:

{
  "cheapest": { "source": "ebay", "price": 26.23, "url": "https://www.ebay.com/itm/307065683170" },
  "cheapestPerSource": {
    "amazon": { "price": 28.99 },
    "ebay": { "price": 26.23 }
  },
  "targetMet": { "source": "ebay", "price": 26.23 },
  "comparableCurrencies": true
}

Prices are compared like for like

• eBay prices include postage. A £0.99 listing with £12 postage is compared at £12.99, which is what you would actually pay.
• Out-of-stock offers never win. The cheapest thing you cannot buy is not a useful answer, so unavailable rows are excluded from the comparison rather than ranked.
• Mixed currencies are flagged, not silently ranked. Pricing Amazon UK against eBay US would compare pounds with dollars and name the wrong winner, so comparableCurrencies comes back false and the run warns you.

Run it as an API

curl -X POST "https://api.apify.com/v2/acts/arched_friend~multi-store-stock-alert/run-sync-get-dataset-items?token=YOUR_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "amazonAsins": ["B0FGJF172R"],
    "ebayKeywords": ["zojirushi travel mug"],
    "titleMustContain": ["mug"],
    "targetPrice": 30
  }'

Pricing

You pay $0.05 for each source actually checked, so a two-store watch costs less than a three-store one.

The source Actors bill their own usage on top of this, because this Actor runs them for you: Amazon Price Tracker at $0.01 per product, eBay Price Tracker at $0.02 per search, Shopify Price Tracker at $0.02 per store. A daily watch on 2 ASINs plus 1 eBay search costs about $0.14 a day all in.

Watching one product across 3 stores daily	Monthly cost
Checking by hand	roughly 10 hours
Most price comparison tools	$30 to $150 per month
This Actor, all sources included	around $5 per month

Common questions

Why did a source come back empty? Each source reports its own status in the run summary, with the error if it failed. eBay occasionally challenges even from residential exits; the source Actor retries on fresh sessions, and if it still fails the other stores are reported anyway.

Do I have to use all three stores? No. Leave any of the three inputs empty and that source is skipped entirely, and not charged.

How does it know two listings are the same product? It does not try to match them automatically, because fuzzy product matching across marketplaces gets it wrong quietly. You scope the run with titleMustContain, which is explicit and predictable.

Where is the price history kept? In the source Actors. Each one tracks its own baseline, so changeType arrives already computed and history builds from your first run.

Related products

• Amazon Price Tracker to watch Amazon on its own
• Amazon Stock & Buy Box Alert to watch who is winning the buy box
• eBay Price Tracker to watch eBay on its own
• Shopify Price Tracker to watch any Shopify storefront
• Amazon Deals & Coupon Monitor to find discounts you are not yet tracking