What do you mean by The more successful sellers have their own templates they use.
When you look at a listing, the design or layout of the listing is called the template.
The bigger sellers Jimmy is talking about are the ones who have created their own design/template.
Looks a lot like a website. If you go to Bestbuy their layout could be called their template.
I would suggest going to Auctiva and registering with them. Its free. They have a lot of nice templates which though not complex or original as other people can use them, they do look nice and are worth using.
I see you mentioned DOBA. You may find their pricing is not very competitive.