Every year our branch gets requests for help with the cost of treating puppies who have not been given the essential early healthcare they need. I am constantly amazed that people may pay out £200-£500 for a pup which is not wormed, vaccinated or treated for fleas and has been taken away from mum far too young. Once they have fallen in love with a puppy the new owners naturally want to do the best they can to help it survive, but often they have exhausted all their spare cash on the initial purchase price.
There can be genuine reasons for wanting a puppy, rather than an adult dog, but, if anything, that means you should take more care to find out about the background of a pup. No responsible breeder will suggest meeting you anywhere other than the place where the puppies were born. A good breeder cares what happens to their animals and will be only too happy to show you vaccination certificates and provide details of when the puppies were last wormed and when the next dose is due.