Why Amazon Is a Primary Research Source for eBay Sellers

Amazon is not just a competitor to eBay — for millions of eBay sellers, Amazon is their primary sourcing market. The Amazon-to-eBay arbitrage model works like this: you find a product on Amazon that is priced lower (or available at a temporary discount), list it on eBay at a higher price, and when a buyer purchases it on eBay, you order it from Amazon and have it shipped directly to the buyer.

This model is called Online Arbitrage (OA), and it requires fast, accurate price comparison data. Chrome extensions make this possible at scale — instead of manually opening 50 product pages to check prices and demand, extensions overlay the critical data directly on Amazon search pages while you browse.

In this part, we cover the two most important Amazon-focused extensions: DS Amazon Quick View and Keepa.

DS Amazon Quick View — The Free Starter Tool

What it is: A free Chrome extension developed by DSM Tool (now Scrybs) that adds an information panel directly below each product listing on Amazon search results pages.

What data it shows (visible without clicking the product):

• Price — Current Amazon price (buy box price)
• Best Seller Rank (BSR) — The product's ranking in its main category
• Star Rating — Average customer review score
• Review Count — Number of reviews (proxy for demand and market maturity)
• Fulfilled by — Whether it's FBA (Amazon fulfilled) or FBM (seller fulfilled)

How to Use DS Amazon Quick View for eBay Research

When you're searching for products to sell on eBay via Amazon arbitrage, you want items with:

1. BSR under 100,000 in major categories (Electronics, Home & Kitchen) — this means the product is actually selling, not just listed
2. At least 50 reviews — indicates the product has proven demand
3. Price between $15–$80 — eBay's sweet spot for impulse buys with good margins
4. Not sold by Amazon directly — if Amazon is the seller, they control the buy box and can undercut you anytime

With DS Amazon Quick View installed, you can scan an entire Amazon search results page and identify potential products in 2–3 minutes, rather than clicking through each listing individually. This is a 10× speed improvement over manual research.

DS Amazon Quick View Settings

After installing, click the extension icon to access settings. The key setting is "Show Panel Position" — choose "Below Image" for the cleanest view on search results. You can also toggle which data points to display, keeping only the fields most relevant to your research style.

Keepa — The Price History Expert

What it is: Keepa is the gold standard for Amazon price history tracking. It has been collecting Amazon price data since 2013 and displays historical price charts, sales rank history, and offer count data directly on Amazon product pages.

Free vs Paid: The free version shows basic price history but limits how far back you can see and how often it updates. The paid version (€19/month) shows complete price history going back years, updates every hour, and includes sales rank history — which is the most valuable data point for arbitrage research.

Reading a Keepa Chart

When you visit an Amazon product page with Keepa installed, a chart appears below the product images. It can look intimidating at first, but here's how to read it:

• The blue line — Amazon's own price (when they sell the product). Gaps in the blue line = Amazon is out of stock or not selling
• The orange line — New third-party seller price (the buy box price when Amazon isn't selling)
• The green line — Sales rank over time. When the green line dips sharply downward, the product had a sales spike (it sold well)
• Red line — Used product prices (not relevant for most eBay arbitrage)

What Good vs Bad Keepa Charts Look Like

Good chart (safe to source): The price line is relatively stable over 3–6 months. The sales rank line shows regular dips (regular sales pattern). Amazon is consistently in stock with a stable price.

Bad chart (avoid sourcing): The price has dropped dramatically in the last 30–60 days (price crash in progress — you'll buy at high, sell at low). The sales rank shows rare or erratic dips (unpredictable demand). Or the product just launched 2 weeks ago (not enough history to evaluate).

Setting Up Keepa Price Alerts

This is one of Keepa's most powerful features for Online Arbitrage. You can set alerts so that when a product drops below a certain price on Amazon, you receive an email notification. This lets you run a "buy low, sell on eBay" system semi-automatically:

1. Find a product with good eBay sold data (use Terapeak)
2. Calculate the target Amazon buy price that gives you 20%+ margin on eBay
3. Set a Keepa price alert for when Amazon hits that price
4. When the alert fires, buy 3–5 units, list them on eBay, and ship when sold

Common Mistakes with Amazon Research Extensions

Mistake 1: Ignoring the sales rank history. A product might look cheap today, but if the Keepa chart shows the price crashed 40% in the last 30 days, you're buying into a declining market. Always check 90 days of price history minimum.

Mistake 2: Trusting BSR without checking eBay demand. A low Amazon BSR means the product sells well on Amazon. That doesn't automatically mean it sells well on eBay. Always validate eBay sold listings separately using Terapeak or ZIK.

Mistake 3: Buying products with many Amazon reviews but low eBay competition. This sounds like a good sign, but very low eBay competition often means buyers aren't looking for this product on eBay — they go straight to Amazon. Check eBay search volume too.

Key Takeaways

• DS Amazon Quick View overlays BSR, price, and rating on Amazon search pages — scan 50 products in 2 minutes
• Keepa tracks Amazon price history — use it to confirm prices are stable before sourcing
• Look for 90+ days of stable price history on Keepa before buying for arbitrage
• Always validate eBay demand (sold listings) even when Amazon BSR looks good
• Keepa price alerts let you automate the "buy low" part of Online Arbitrage
• Never source a product whose Keepa chart shows a price crash in the last 30–60 days