How FlipLens works

1. Identify the exact product

You take a photo of the item or its label, scan the barcode on the box, or type the model. Photos are identified by an AI vision model; barcodes (EAN and UPC) are matched against marketplace listings. FlipLens looks for the details that change the price: model generation (WH-1000XM4 is not XM5), storage (128 GB is not 256 GB), lens mount (RF is not EF) and condition. You can correct anything before the check runs.

2. Find comparable listings

FlipLens searches current eBay listings in Germany, France, Italy, Spain and the Netherlands through the official eBay API and converts prices to euro with European Central Bank rates. It then filters out what would distort the price: other models and variants, accessories sold on their own, bundles, broken or "for parts" items, duplicates and listings in a very different condition. You can see every listing that was used and why others were removed.

3. Estimate the resale value

From the remaining listings FlipLens builds a price distribution adjusted to your item's condition and reports three numbers: a quick-sale price, the expected sale price and a high asking price. Because asking prices are usually above final sale prices, the estimate is adjusted down. Every estimate carries a confidence score based on how many listings matched, how much they agree and how well the product was identified.

4. Calculate profit after fees

FlipLens subtracts the selling fees of the marketplace you sell on (for example eBay.de private or business, Vinted or local pickup), your shipping cost and the purchase price. The result is profit, return on investment (ROI) and the maximum price worth paying for your target ROI: max price = money you keep after fees and shipping ÷ (1 + target ROI).

5. Give a verdict, or say it does not know

The verdict is strong buy, buy, borderline or skip, with the reasons and risks behind it. If fewer than five matching listings remain, or the product identification is too uncertain, FlipLens says "not enough market data" instead of inventing a number.

Known limits

• Prices are based on active listings (asking prices), not on confirmed sale prices.
• Supply is visible (how many items are for sale and for how long), sell-through speed is not yet.
• Fashion, collectibles and one-of-a-kind items are not supported.
• Fees change: each fee profile shows when it was last checked and links to its source.