Small Tools, Big Difference
The gap between resellers who make decent money and resellers who consistently make great money usually isn't about finding better stock or selling on more platforms. It's the small operational edges — the 2% saved here, the 30 seconds shaved there, the discount code you'd never have found manually. Compounded across hundreds of transactions a year, these add up to thousands of pounds.
Most of these edges come from browser extensions. They run quietly in the background, cost nothing, and improve your margins or efficiency on practically every transaction. Here are the ones that UK resellers actually use daily.
Coupert — Automatic Discount Codes at Checkout
This is the one that pays for itself the fastest.
What it does: When you reach a retailer's checkout page, Coupert automatically scans its database of discount codes and tries each one to find the best available deal. You don't search for codes, you don't copy and paste anything — it just runs through them in seconds and applies the one that saves you the most.
Why it matters for resellers: You're checking out from online retailers constantly — restocks, clearance sales, new releases. Even a 5–10% discount code on a single stock purchase improves your margin on every unit from that order. Across dozens of purchases a month, the savings are substantial.
Coupert also has its own cashback programme on top of the discount codes. When you make a purchase at a supported retailer, it tracks your order and credits cashback points to your account that you can redeem for PayPal cash or gift cards. So you're potentially getting a discount code and cashback on the same purchase.
Setup
- Create a free account at coupert.com
- Install the browser extension (available for Chrome, Firefox, Edge, and Safari)
- Shop normally — Coupert activates automatically on supported retailer pages
TopCashback — Earn Money Back on Every Stock Purchase
We covered this in detail in our dedicated cashback guide, but it belongs on this list because it's one of the highest-impact tools available to resellers.
What it does: TopCashback partners with thousands of UK retailers. When you click through their tracking link (or activate via the Chrome extension) before making a purchase, you earn a percentage of the sale back as cashback. Rates typically range from 1–15% depending on the retailer and any active promotions.
Why it matters for resellers: If you're spending £500+ per month on stock from online retailers, even 3% average cashback returns £180 a year in pure extra profit on purchases you were making anyway. The Chrome extension means you never forget to activate it — it pops up a reminder whenever you're on a partner retailer's site.
Sign up free at topcashback.co.uk and install the extension. That's the entire setup.
Google Lens — Instant Price Checks While Sourcing
What it does: Point your phone camera at any product and Google Lens identifies it, shows you where it's sold online, and gives you current pricing across multiple retailers and marketplaces.
Why it matters for resellers: When you're sourcing in person — charity shops, car boot sales, clearance aisles, wholesalers — you need to check whether an item is worth buying before committing. Google Lens gives you an instant reality check. Snap a photo, see what it sells for on eBay, and make a buy/pass decision in seconds.
It's built into the Google app on both iOS and Android, and available in Chrome on desktop. No separate installation needed.
Terapeak / eBay Seller Hub Research — Know Before You List
What it does: Built directly into eBay's Seller Hub, Terapeak shows you historical sales data — what items sold for, how many sold, average prices, and sell-through rates over the past 90 days.
Why it matters for resellers: Before you list anything on eBay, Terapeak tells you whether it's actually selling, what price to expect, and how competitive the category is. This prevents you from listing items that won't move and helps you price competitively based on real data rather than guesswork.
Access it through your eBay Seller Hub — it's free for all eBay sellers. Go to Research → Terapeak Product Research.
Keepa — Amazon Price History Tracking
What it does: Keepa adds a price history graph directly onto Amazon product pages, showing you how the price has changed over weeks, months, or years. It also lets you set price drop alerts for specific products.
Why it matters for resellers: If you're sourcing from Amazon or selling via Amazon FBA, Keepa is essential for understanding whether a product's current price is genuinely good or just average. A product listed at £25 might look like a deal, but if Keepa shows it regularly drops to £18, you know to wait. Conversely, if the price has been climbing steadily, it signals growing demand.
The price alert feature is also useful for buying stock at optimal prices. Set an alert, wait for it to drop to your target buy price, and purchase automatically at the margin you need.
Install the Keepa browser extension (Chrome or Firefox) — the basic features are free.
eBay Sold Price Extension — Real Market Values in One Click
What it does: Several browser extensions (like "eBay Sold Price" or similar tools) let you quickly view completed/sold listing data on eBay without manually changing search filters every time.
Why it matters for resellers: Knowing what an item actually sells for — not what it's listed at — is fundamental to making profitable buying decisions. These extensions save you the repetitive steps of filtering by "Sold Items" on every search, making price research significantly faster.
This is especially useful when you're rapidly evaluating multiple items during a sourcing session and need quick price checks.
uBlock Origin — Cleaner, Faster Browsing
What it does: Blocks ads, pop-ups, and tracking scripts across every website you visit.
Why it matters for resellers: This might seem like a strange inclusion, but if you're spending hours a day browsing retailer sites, checking stock, and managing listings, a cluttered browser full of pop-ups and auto-playing video ads slows everything down. uBlock Origin makes pages load faster, removes distractions, and generally makes your work more efficient.
The Extension Stack That Covers Everything
You don't need dozens of tools. These six cover the core bases:
- Coupert — automatic discount codes + cashback at checkout
- TopCashback — referral cashback on purchases (free signup)
- Google Lens — instant in-person price checks while sourcing
- Terapeak — eBay sales data and pricing intelligence (built into Seller Hub)
- Keepa — Amazon price history and alerts
- uBlock Origin — faster, cleaner browsing
Install them all once, and they work in the background on every session. The combined effect is less money spent on stock, better pricing decisions, and faster workflows — all of which directly improve your bottom line.
These tools optimise the transactions you're already making. But knowing which products to buy and when to buy them is where the real money is. That's what ResellRadar's real-time drop alerts and product intelligence are built for — getting you to the profitable stock before everyone else.