There are a few that should be considered. Amazon, eBay, and Walmart to start with. They typically take 15-18% of the sale as their commission, and the clients belong to them - technically not you. But if your profit margins are high enough, or you think you can do enough volume, they can produce an income for you.
Amazon.com
The largest and will likely produce the most results, but there are caveots to using them.
eBay
They have been around the longest, and they still produce quite a few sales - both for used and new product.
Walmart
Much smaller than Amazon and will take some effort to get your products listed on their platform due to ongoing technical issues.
Sears
Surprisingly, they still exist online, and their exist possibilities to list your items there.
Product Feeds
Google Shopping is the largest known today, but some of the old ones still exist: Shopping.com, Nextag, Shopzilla, Pricegrabber, etc.
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