Well, for one thing, all of the components inside the engines have their own life limits. It's not just a single hour limit for overhaul-- every wheel in there has a cycle limit as well. Of course, in this case, who knows how many cycles it has on it?
I think anyone considering this airplane should go back and read Bruce's comments about it on earlier pages of this thread. Note, in particular, that he couldn't even be sure of the serial number of the airplane!
You might ask how that's possible. Well, the answer is that several 980s (and other Commanders) were stolen, taken to south america, and used for drug running. Switching the serial numbers around to make them more "legitimate" was as easy as swapping the data tag. Now, I don't know if that was the case with this particular airplane, but it's not out of the question.
All of that might be okay, with the proviso that it's cheap when you buy it, and it will be cheap when you sell it... but that's just the airframe. The engine are a different story.