question

Hi @carid,

You can use the Trading API or Inventory API to list the item. Trading API is our legacy API which support XML and SOAP format while Inventory API is our new API which supports REST format. If you wan to use Trading API, you can use the following calls:

Ref: https://developer.ebay.com/devzone/xml/docs/Reference/eBay/StandardListingIndex.html

If you want to use Inventory API to list the item, please go through the link given below to see the API flow.

Ref:https://developer.ebay.com/api-docs/sell/static/inventory/inventory-item-to-offer.html

Please go through the link given below to see the flow of quantity and price updates via Inventory API.

Ref: https://developer.ebay.com/api-docs/sell/static/inventory/bulk-updates.html

Best regards ,
eBay Developer Support

This call creates new listings against the specified SKUs. If the SKU already exists in the system, then this call will overwrite the listing information associated with it. The rules for listing a product in the marketplace are subject to change, so it is recommended to handle errors explicitly. It is also recommended to call upon the validate API (to be announced) prior to making this call.

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