Walter,
Like I mentioned on the phone. Plenty of people selling dogs to make a buck. Maybe what they mean by finished dog, is that they are finished fooling with it.
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There are some great dogs out there, but I am willing to bet
most of them will never make it to a classified section.
I have bought more dogs than I care to think about. Some worked, most didn't. I think more often than not though, people were not intentionally lying about the dog, they just did not know the dog nearly as well as they thought they did.
I have had more success buying dogs that I have hunted behind, but are "not for sale" which usually means I really don't want to sell this dog, but if you put enough bills in front of me, I will sell the dog