If this is not going to be a hunting dog, go to the pound or humane society. \
No reason to shell out big bucks for a specialized animal when a mutt can do the job just as well.
The average dog owner does not have the time, experience or the knowledge to rehabilitate a problem dog.
I'd add that often problems don't show up to the people at the pound. Our latest dog was "cat tested" by the humane society, meaning he got along ok when exposed to cats at their kennel. When we brought the dog home he immediately tried to attacked our cats. It took a lot of time to get him over that.
My wife and I are not experts with dogs. What we do have is lots of time.