I buy the ones that look like that for $1000 used. When it's time to get another one I sell it to a mechanic that knows how to get it running again, and he resells it or uses it. And I have a little money to put on the next one for myself. Logger is right about being able to fit the little grinders in tight places. They're a must have. If you have a few of them, you can get a few groundies on a group of stumps at a time, and it doesn't hurt your wallet too much to manage that.
The ones that I buy have a 13HP Honda in them, and they look exactly like the one in your pic. One thing suspicious about your example there is that it looks like it says 13HP on the handles, but the ad is boasting of 15HP. And I have never heard of a Lifan motor. Unless you have the money to lose experimenting with a Lifan, I would save it for a 13HP Honda motor on the same style of deck for around a $1000. And test out your stump grinder before you buy it, or you could be buying junk.
