Make sure all their dogs are inside, and clean. The pups should be healthy and hyper, not fearful or dirty. You want the litter to be raised in the house, and of had lots and lots or interaction. They should of all ready been exposed to grooming, having had at least two full baths and blow drys and some clipper work to expose them to it early. The pup MUST be eight weeks old before it goes home with you. Be sure the litter has had proper worming and shots on time. The pups should be exposed to crating, and ideally have spent a few nights already in one alone.
The parents should be friendly, some barking is ok but not prolonged or any growling or avoiding you. Do NOT let them detour you from seeing both parents, some people will hide the snappy mother/father and avoid letting s/he be seen.
The parents should have their eyes tested, and both checked for slipped stifle to be sure your getting the best pup possible. These two are the most common problems both breeds share. Their should be no epilepsy in the lines, it's not testable but is genetic, so your breeder should have info on the parents of her dogs for generations back.