Oh, dear. Before you adopt a dog from a Pet Store, ask where they get their pups. If they say "From a breeder," ask if you can get the breeder's contact info so you can see the parents. If they say "no, the parents aren't local" or "No, we get them through a broker" or any other "No," they are probably puppy mills dogs. As sweet as that chihuahua is, you do NOT want top support those horrible places, right?

If you continue with it, ask if you can take the pup to a vet before making any commitment. If they say "she's just been to a vet," ask to see her records. Again, if they balk ...

Sorry to put a damper on it. Go on Petfinder - I'm sure there are lots of needy pups in shelters!