I'm with Whatisit on this one. Even if the oil doesn't show any problems now, an OCI of that long can't be good for a turbo, especially with the problems already associated with these turbos. Car might be fine now, but as poorly maintained as it was, the life of that turbo will most likely be cut short. Could end up being fine for years, but I wouldn't chance it. Take your time, find a car with low miles that's been taken care of, and the extra time you take will hopefully pay off with a reliable, fun to drive car.