I've been a breeder for 28+ years and will not let a sick puppy leave my home.
I insist that any puppy get checked out by your vet within 3 days to confirm this. If your vet discovers a problem that will lead to death, the puppy will be replaced as long as documents are provided.
However I can't be held responsible for minor issues such as coccidiosis, ear mites, worms or hyperglocimia which can be cured with treatment.
As far as size or color at maturity, I can only guess at that.
I also can't guarantee the puppies will be suitable for breeding purposes...sometimes the females can be too tiny to experience motherhood. I haven't had a problem with the male's testicles not dropping, although because of their size it just may take longer to mature. puppies are guaranteed to be healthy before leaving.
Please keep me updated about any other issues involving your puppies health.