Many eCommerce retailers are working with multiple distributors that can fulfill the same products. Each distributor has a different level of stock on hand, product price and other fulfillment fees.
In many cases retailers have an internal warehouse or 3PL where they can fulfill the same products from.
The trick to working with multiple supplier for the same product is that product data needs to be tracked at both the product and vendor level.
Here's the data you need to track