Hello,
I have more than 7 year experience of Google analytic. I had done this in past for one of my client.
Now question is what i will do for you.
I will give you one piece of code. You need to place this code. You need to place this code on every ebay listing page. You have to follow my instruction while placing code (You need to replace item ID code on every single listing page.)
Remember given solutions is limited in its data collection so you will not get all analytic data but you have limited data to track no of users, source of user etc.
You need to release payment once Google analytic will show some data.
Thanks
Manish