Sometimes it makes more sense to use a pre-made sales site rather than set up your own website if you're just getting started in sales. Sometimes you've got a website, but you want to handle sales separately. And sometimes a selling site makes sense because of the extra traffic it can help generate.
Please don't think that using a selling site is a free ride though. They are not going to automatically bring the buyers to you...you will have to dedicate time and energy into promoting your online shop, or nothing will happen. Count on it!
Don't let the fact that the first link on my list talks about places to buy handmade make you think you've gone to the wrong place...
10 Great Websites to Buy Handmade Goods
Setting Up Shop: Handmade Marketplace Comparisons
Online Venues for Selling Crafts and Handmade Goods
Starting an Etsy Business
Free Ads for Your Etsy Shop
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