It isn't a great deal. Similar domestic kegerators are 150 more or so in the store. If it is in excellent shape I think it is a fair deal.
I can't tell from the picture, but does that have the compressor hump running the length of the back or just in one corner? That tends to make the difference between 2 and 3 cornies getting in there (some of the commercial models have the compressor underneath and you can get four, I see them on CL sometimes for around the same price but older).