Normally, they advertise the products on their websites or any selling sites and when a customer pays for it, the item is ordered and paid by the owner to producer.
It will save you having to put your items and carry them for the post working. https://ourdailyglass.com/__media__/js/netsoltrademark.php?d=brandafy.com%2Fblog%2Fshopify-store-names%2F