Well, buying pets online is not bad but it can be risky because all the breeders are not honest and good to the animals. I personally think online buying is okay for buying clothes and accessories. I will prefer buying pets offline.It is my personal thought though. I think you can be on the safer side if you follow these guidelines
1. meet the breeder and puppy physically.
2. meet the puppy parents and check their health
3. Do Not make the payment in cash
4. check if the site has any authentication measures for the breeders.
5.chose the classified sites which has some measures to help the buyers to have a good buying experience. Those sites have most of the genuine breeders registered there.
6. A good breeder will ask a lot of questions about your home environment.