How to check whether an eBay listing clears your profit line on Amazon

What you need before you start

1. An Amazon seller account in good standing. A Professional account makes sense if you plan to sell more than a handful of items a month, since the Individual plan charges a per-item fee.
2. A list of products. The method works best when you start from products you already sell, or products you have researched and know the ASIN for. Browsing eBay with no list of targets is slow, and mistakes cost more.
3. Approval for your categories and brands. Amazon restricts some categories and brands. Check in Seller Central that you can list the product in the condition you plan to sell it, before you buy a single unit. Approval can take days.

A useful habit is a short list of 20 to 50 products you know well: the model number, the usual Amazon price, and the common ways a listing can be wrong. A short list you know beats a long list you do not.

Step 1: match the listing to the exact ASIN

Most losses in this method come from a wrong match, not a wrong price. An eBay title is written by a seller in a hurry. It may leave out the model number, name the wrong generation, or describe a kit when the item is a bare tool.

Match on identifiers, in this order:

1. UPC or EAN, if the listing shows one in the item details.
2. Manufacturer model number, from the title, the item specifics and a photo of the label.
3. Brand and product name, only as a last resort.

Then compare the form. A bare tool and a kit are different Amazon items. So are new and used, a two-pack and a single, and one generation and the next. If the listing does not show which one it is, ask the seller or skip it. Our guide to reading power tool model numbers shows how much one suffix can change the match.

Step 2: do the fee math

Work out profit from the Amazon side, with the eBay asking price as your cost. Write down every line:

Amazon sale price
- Amazon referral fee
- fulfillment or shipping fee
- other Amazon fees (storage)
= Amazon proceeds

eBay asking price
+ eBay shipping to you
+ sales tax you pay
+ prep and inbound shipping
= your total cost

profit = Amazon proceeds - your total cost
return = profit / your total cost

Use the real Amazon fees for your item. The referral fee is a percentage that depends on the category. Use Amazon's own fee preview for the exact item, not a number from a blog post.

Count the shipping. eBay shipping to you is a cost. So is shipping to an Amazon warehouse if you use FBA.

Count tax. Depending on where you live and what you buy, tax can be a real cost. Ask your accountant.

Use the Amazon price you can expect to receive, not the highest price you have ever seen. Look at the price over a few weeks, not one day.

Step 3: check condition rules and approvals

Amazon has rules about which conditions you can sell in each category. New items usually need to be new in the original packaging. Used items can be sold only where the category allows, and often need to meet a stated condition grade.

1. Can you list this ASIN in the condition you will receive?
2. Is the brand or category restricted for your account?
3. Does the product carry restrictions such as hazmat rules or size limits?

Be careful with "open box" and "new other". Those do not map cleanly to an Amazon condition. When the photos do not settle it, treat the item as used.

Step 4: check new listings often, with your rules decided

Good listings attract other buyers, so the earlier you see one, the better your chance. There are two ways to keep up.

The manual way: save a search for each target product, sort by newly listed, turn on eBay's notifications, and check on a rhythm. It costs nothing and it works, but it depends on your attention. See eBay saved searches compared for how eBay describes its own alerts.

The automatic way: a tool that watches new listings for your products and tells you when one matches. We cover that below.

Either way, decide your minimum profit and minimum return before a listing appears, so when one does you only have to check the match and the photos.

Keep the worksheet from Step 2 in a spreadsheet, one row per listing, with a column for your decision and one for what happened. Once a week, drop products that produced nothing in a month and add ones where you wished you had bought a second unit. After a few weeks the sheet shows which products and conditions actually clear your profit line.

Step 5: buy by hand and keep records

Buy the item yourself on eBay after you check the listing. Read the seller's feedback, look at every photo, and read the description for words like "untested", "for parts" or "missing". Ask a question if anything is unclear.

1. Save the eBay order confirmation and the payment record.
2. Keep the shipping confirmation and tracking number.
3. Record the date, the ASIN, the cost, and where the item went.

Items bought on eBay come with eBay order records, not retail invoices. Some sellers report that Amazon asked for invoices during an account review, and that eBay-sourced inventory made those reviews harder. We cannot promise how Amazon will treat your account. Start small, read Amazon's current rules for your category, and keep every receipt. This is not legal advice.

Where a watcher helps

Steps 1, 2 and 4 are repetitive. That is the part MarginPing is built to take over, starting with power tools and tool kits.

MarginPing works from your own product list. You upload the All Listings Report from Seller Central, or connect your seller account with read-only access if you prefer live prices. It watches new eBay listings for those products, matches each listing by model number and UPC, reads kit versus bare tool and lot size, works out Amazon fees and your estimated profit, and sends a Telegram message when the profit clears the line you set. Each alert shows when the listing appeared and when we sent it.

It leaves Steps 3 and 5 to you. It never buys, bids, or messages a seller. MarginPing is in final testing and not open for signups yet. See power tools for the category we start with, or the eBay sourcing tools roundup to compare options.

Questions