Buying a dog that is not on a deworming regimen?

So I went through AKC to find a Yorkie. I have been talking to this lady and I'm going up to see the dog this Saturday. She says she doesn't deworm her puppies because she doesn't want to "poison them" (her words not mine). However she does do stool samples. I just want to know if this should be something to consider if I buy him. Don't get me wrong, if I buy him I WILL start him on a deworming regimen. I just want to know if I buy, will the fact he hasn't been on a deworming regimen will cause problems. I just want to start off with a healthy dog.