I have someone wanted to do some trading. He has a 8540 open station, 4x4, with loader. I don't know if it is sync or hyd shuttle. I have not seen it yet. He says it has 3500 hours. I am interested in a tractor of this size, also, I will not put many hours on in a year(maybe 100). At this many hours, what are common things I need to look for? What is the longevity of the motor, hydro pumps, etc? Approximate value of tractor?