What should the adverage mark-up be when selling an item on Ebay? -

i think it should be 37% because its a pretty cool number and the mark up should be always under 50%, it will be different per item but it should never be over fifty unless its really weird.

No, they all wrong. It should be the other way around. If the products you sell is available in local stores, then, your selling price should be at least 35 to 37% lower than the market price because customers have to pay shipping cost as well. Why would people buy on eBay when they could buy it at their local stores unless they can get a bargain online.Selling on eBay is different from selling your products in the stores. People only looking for things that are cheap unless it is something they cannot find from local retailers.

Traditionally a fair markup in business is 35%. It has to vary with the item, but that is a good starting place.