How to evaluate a Marketplace listing using sold comps

Worked example with invented inputs. This is a research walkthrough, not a customer result, verified sale, or claim that Find & Flip produced this exact valuation.

1. Establish what you would actually buy

Suppose a Facebook Marketplace seller asks $160 for a used Nintendo Switch OLED with its dock and controllers. Confirm the OLED model, working condition, included charger, screen condition, and whether every accessory is present. An asking price is not a completed purchase.

2. Compare equivalent sold listings

For this example, assume four observed sold-listing prices for comparable used, complete consoles: $210, $220, $230, and $240. Exclude a $300 bundle with games and a $90 damaged console because they are different offers. Check sold dates, shipping treatment, and currencies. An accepted offer can differ from the displayed source price.

3. Subtract costs before calling it profit

At that purchase price, estimated return on purchase cost is $8.70 / $160 = 5.4%. If resale falls to $190 with the same assumed fee rate and shipping, estimated profit becomes −$8.70. A large gap between asking price and sold prices can still be a weak deal after costs.

4. Use the evidence in Find & Flip

The Deal Finder lets you inspect relevant sold comps alongside estimated value, profit, and deal scores. Strict matching narrows which results count as comparable; it cannot verify an item's condition for you. Review the evidence, change assumptions where needed, and pass on the listing if the remaining uncertainty is too large.

Developers can use the eBay sold-listing API to retrieve source records and implement their own matching and fee calculations. The raw API does not promise the app's AI valuation or matching workflow.

Explore Find & Flip

Marketplace Deal Finder for Resellers · A worked resale valuation · Full API documentation