On my pup? It's not like I just picked him up out of the blue. Didn't mean it to sound that way. His parents had physical documentation for all OFA scores and competition titles as well as references for other customers who had gotten puppies from the same breeder and gotten positive health checks and titled their pups in various sports, many of which I was actually able to call the owners and confirm. I also visited the parents themselves several times on site and saw for myself their general temperament around other dogs and strange people (which was calm but aloof, just as it should be). While he may have been on the cheaper end which usually isn't indicative of high quality, I was provided the documentation to back up their dogs. In my experience, I've never run into health or temperament problems with runt of the litter puppies, so I was not concerned about that.
I didn't mean that all $1000 puppies are just fine, just that you can always check them out and see if they may be one you would be comfortable with. It doesn't have to be a $4000 champion bloodline dog to be a healthy, stable dog. That may be what someone looks for if they want say a serious sport or confirmation dog, but that depends on the OP's goals with the dog.