The seller needs to show that their items are unique by making them to order at a customer's spec. Keep prices down by not starting each item from scratch, but customizing a base product.
You make rings? Have a bunch of nice rings that you resell. Maybe even import them from China and sell on your store. But build your reputation by providing customized versions of those rings. Not by simply printing the buyer's name on them, but changing the type or number of stones, the metal, thickness, how the wiring is knotted, etc. Those are all ways to stand out from the high-volume crap and still keep the price reasonable.