I had a brief career as an online merchant using E Bay and Craigslist, primarily. I found that the best pictures win overall. If you can make your ad pictures just a bit more professional than the usual cell phone pictures or the fella' that thinks he doesn't need to clean up the background, you'll do well. Lighting is another thing that makes small items or closeups that much better.
My record sale was a Gucci eyeglass case that sold in under 10 seconds from listing. I positioned the eyeglass case on a dark velvet background and positioned a red rose beside it. It was like fishing with leeches for walleyes, they just can't resist the presentation.