What model year? Can he visually inspect it? If he can, then hopefully he can start it, operate it, and look at the hour meter. He should also ask for the maintenance history.
If nobody knows anything about it, then something isn't right.
There certainly are none in the engine oil, but we also don't know how many hours are on the oil. The engine oil looks close to virgin, so nothing can be learned from it. I can't comment on the hydraulic oil.