I have not heard of people listing things for other people before, but I'm sure that it probably does exist - but it shouldn't be too hard to replicate the idea, it definitely wouldn't be protected so would be completely legal.
The ability to make a profit depends on everything else. If you spend no money on advertising (which would surely be the only cost considering you have to buy no stock) then surely all income is profit?
You will probably want to work out the numbers yourself - but I would recommend a commission rate of between 8-15%. After all, you need to make it worthwhile for the people letting you sell, considering they are essentially giving you the items for free. eBay also take about a 10% commission - so this means your client will only be receiving about 75-82% of their money after both of the fees are removed.
Hope this helps,
Luke
Luke
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