If you import non-proprietary (i.e. non-patented) products then building competitive advantage for your products can be challenging. Your competitors can import nearly identical products as you, possibly even from the same supplier as you. However, there are ways to separate your products from your competitors in these cases.
- Stand by your products. Replace or warrant defective products. Be overly generous in accepting warranty claims.
- Provide instructions, how-to's, and other product literature.
- Develop excellent product packaging and/or product photography/videos
- Provide accessories with your products or package them in multiple quantities
For the first point, you are bound to sell a product that fails for a customer. Sometimes it will be because of a clear product defect and sometimes it will be because a customer misuses the product. If it's the former, then make it easy for the customer to get a replacement. If it's the latter and there's any doubt about whether it's a customer misuse issue or product defect issue, than err on the side of caution and give the customer a replacement. If you don't stand by your products, your customers won't.
Second, many product importers are guilty of providing products with a brown box and nothing more. All products deserve some instructional materials that direct the customer in proper usage, assembly, etc. Your supplier likely won't provide these, so you must yourself.
Third, include packaging beyond a brown box, especially if you're selling in brick-and-mortar. If you're selling online, you might be able to get away with near non-existent packaging but it better be backed up with exceptional photographs, videos, and other media.
Finally, consider including accessories with your products when possible or selling them in multiple quantities. For example, if you import brooms, package dust pans with the brooms. Packaging products together immediately differentiates you from your competition if your competitor requires the consumer to purchase two products in two different locations. You can create similar advantages by selling products in multiple quantities. You can likely achieve economies of scale by selling 2/3/4/etc. widgets in one sale opposed to an individual widget and subsequently pass these savings on to the consumer while maintaining your profit margins.
This list is of course far from exhaustive but it goes to show that you can differentiate your products, even if they are commodities.