Well, it is a 6 year old machine, been used commercially. In my opinion, he is a little high for what it is. But, that is me. The Kohler engines, if taken care of, with the proper and correct oil, is a very reliable engine, I have seen those engines run over 3000 hours, but, the normal is 1500-2000 hours. Really not anything bad, Exmark makes a good machine, belts are pricey when broken, most all parts are pretty high priced. Check the deck bearings, as most some Exmark products do not have replaceable bearings, if they go bad, you buy spindle asm, not cheap. see if they will let you mow with it, see how the pumps respond, they should be quiet, not noisy or whiney, should work real smoothly.Deck should run without any vibration, clutch should snap in and out very quick, no delay. If you start the engine and it has lifter tap, then I would be a little concerned, as it does have hydraulic lifters in it and if the machine has not had proper maintenance, that can happen.