Some pet centers will not take particular breeds of dog or pets that are ill or have a history of aggression or running away. This is usually due to liability issues as well as safety of staff, visitors, other pets as well as your pet.
Find out about staff turn over at the pet center. If the staff is fairly consistent you can be assured that your pet will get to know the staff and handlers, making being left at the pet center or just visiting for grooming and vet checks more personal and less anxiety causing for the pet.
A doggy day care is often part of a pet center that can allow you to leave your dog, puppy, kitten or cat or almost any other type of pet with the center. If you are housetraining this is a very valuable asset as training can be much more consistent.
