This is why I say I would approach it with a great deal of caution, these will go for what the market will bear, look at this one, rough puppy, the one you showed earlier looked far better yet they dropped to 1000 buck? There is more than meets the eye, on the one I rebuilt we found a crack on the head stock and a broken gear and to replace both proved very expensive. the motor can be expensive as well, even to rewind.
My wife and I owned a ford truck once, put 560000 miles on it and when in threw a rod my wife said should we replace the motor? my answer was NO, the rest of the truck will still have 560000 miles on it and I would be chasing issues caused by putting a new motor in it with more power and torque.
I am not saying it isn't a good deal nor that it isn't worth it. I am not even trying to talk you out of buying it. I am simply advising an abundance of caution and skepticism; because "sometimes" it really is cheaper to buy a new wagon than it is to rebuild the old one.