I have sold products on eBay since 1998. It is a serious hobby!
I sell what I like. I like books, computers, software, cell phones, jewelry (watches & rings), tools, and other consumer electronic devices (like video cameras.
For years, I have searched for a simple market research app that would easily let me determine what sells best on eBay.
I found it today! It is called MarkSight Research Tools Application.
This browser-based app has a free version - which allows you to research eBay completed listings during the past 7 days, and see information on sold items.
For example, I have recently discovered Roku 2 XD Internet streaming devices, and have bought several for my home. Here is how they have sold for the last 7 days ...
Here is a chart of the same info (which lets me identify sales of the latest Roku 2 XD model (Model 3050x - 2 of which sold for average & median prices of $50.99)) ...
The app also has a "Gold" version - which provides you with eBay's top sell-through (defined as # sold items / # completed items) item lists. No need to guess anymore about which items sell best!