Anyway. Are you going to pick up your new dog? I hope you are driving yourself to his location. Don't accept a dog to be shipped at this time.
When you arrive, ask to see the dog where he stays, most of the time. He should be in a pen, or run, or something where he is alone. If he is in with a bunch of other dogs, and is usually kept that way, You may have a bunch of problems with him being "feral", or acting as if he has not been domesticated. When we keep pups for potential buyers, or for ourselves, at 10 weeks they are separated into their own living quarters, out of sight and smell from their other littermates, if there are some. The stress of being removed from their pack needs to happen before 12 weeks of age.
If he has been kept by himself (being let out to play, or kenneled occasionally with other dogs is all fine) Take him to a place that the owner/breeder can say that the dog has never been, or very rarely has been. I have several places on my property that people can take potential dogs to evaluate. If the breeder has no such place, see if he would mind you taking the dog for a short ride to a nearby parking lot, park, etc. You NEED to find out if the dog is environmentally ok. If he has been kept in the same kennel since birth, you will see an ENTIRELY different dog when in a new environment. Stressing out at first is normal, but for how long? A seven month old should start to move about his new area in less than two minutes. If he is still shocky, hiding, or slinking along the perimeter (fence, wall, etc) he is going to be a pistol to do anything with other than a family pet.
Watch him carefully as he interacts with his owner, and then with you. Is it similar? Does he look the owner in the eye? What about you? Does he follow any sort of commands? Will he do that for you? Can the owner walk him on a leash? Can you? If I have a green dog for sale, there are things that he/she does reliably for anyone. For example, if I have a good drug dog prospect, at seven months, he/she plays ball with a vengeance... and will play ball with anyone who can throw or hold a ball.
Hope this helps... you just may have a diamond on your hands!!!!