If you see this kind of advert it is probably a PUPPY FARM
Do not fall for adverts like this.
If they are offering more than a couple of breeds at most then it's probably a puppy farm
If puppies are "frequently available" then it's probably a puppy farm
Report it to your local authority's Animal Welfare Officer or dog warden.
Reputable breeders seldom breed more than one or two breeds of dog and will not usually have more than one or two litters per year available.
If they are reputable breeders then there will probably be a waiting list for their puppies.
There are nearly always waiting lists for the most popular breeds such as goldies, labs, spaniels etc. from reputable breeders.
You are taking a big risk if you try to queue-jump by answering adverts like this one.
Puppies from puppy farms usually suffer poor health and have bad temperaments.
Don't give these people your money. Don't let them get away with it.
(and no, we don't sell puppies).