Started is a loosely defined word. It can mean they just threw a saddle on him once, but it could also mean he's had 30 days of training. It depends on the seller's definition of the word.
I agree with this. You don't really know what started means for this specific horse. I would suggest contacting the seller if you're really interested and asking for some more detailed information. If he's in your personal price range and you have the experience to work with a green broke horse than go check him out and see what you think. It's worth the try. He looks very well put together, although its hard to tell since he's running. You should probably ask the seller for some conformation photos. And it is kind of pricey for an unreg. Horse that is barely broke. I don't know, its still worth a shot.
"'For I know the plans I have for you,' declares the Lord. 'Plans to prosper you and not to harm you, plans to give you a hope and a future'" ~ Jeremiah 29:11