DO provide a product link to an external website. This can be your own ecommerce site.
DO look at this link to view valid websites: What websites can I use for my product link?
DO look at how to upload a product link with this link: How do I add a product link?
DO have the product link match the submitted product.
DO have the product link go to your specific product.
DO have the product link price match the market rate.
DO have the link include http://
DON’T use eBay as the product link.
DON’T have your link go to the general e-commerce platform.