One auction. Eight systems. 100+ hours.

ATG grew through acquisition, so every marketplace arrived with its own back-office tools, workflows, and limits. Publishing a single auction meant working across multiple systems and repeating the same steps in each — building catalogs, uploading photos, writing descriptions, managing bids, invoicing, and arranging shipping. For high-volume sellers, that added up to more than 100 hours per auction.

The Seller Portal brought all of it into one place, letting sellers build a catalog once and publish across all eight marketplaces. I led the design, working with two design peers to audit each platform for shared patterns and conflicting logic, and focused on the pre-auction experience — inventory management and auction creation, where sellers spent the most time. Setup time dropped roughly 60%, giving sellers their hours back to list more lots and drive more GMV.

Here are some mocks from early explorations: