Creates a new inventory item (product) on eBay using the Inventory API. Requires marketplaceId and a unique sku. The SKU becomes the product's permanent identifier for offers, updates, and variant groups.

How to update an existing eBay product's inventory and price

If your listings were created before using the Inventory API, follow these steps before updating:

1. Fetch your product listings using the Get Product Listings resource to retrieve current items and their SKUs.

2. Verify SKUs and migration requirements. Ensure all products have SKUs assigned and comply with the eBay Migration requirements.

3. Migrate listings using the Migrate Listings endpoint (POST /api/v2/products/listings/migrate) to convert them to Inventory API compatible format.

4. Update inventory and price using the Update Product Inventory & Price endpoint (PUT /api/v2/products/{sku} with inventory: true).

More information about the eBay resource.