When researching bitches try this:
Find bitches with the most FC-AFC's etc on the bottom (bitch) side of the pedigree.
When you find one that looks good like above see if she has been bred before and if any offspring have done anything.
Next is to look at the her "Vertical" pedigree. Both for clearance trends and performance results and which sires nicked and which didn't.
That is, what have her siblings done or produced. Often not much info there for young ones so look at bitches mom & grandmom and their littermates and their offspring. did any title? did any do well but not title? are there many offspring not in OFA database? etc..
So, for the above linked dog, she was a good one, FC-AFC, Double Header Winner as a 3 year old, produced field champions etc,
She has a half sister (same mom) that has produced at least 1 FC. Good sign.
and she has a full sister from an earlier breeding that had a stellar career and has produced dogs doing good things.
so, in this example you would write a big check for a puppy, if you could get one.
It's a big gamble and even puppies from rather good breeding don't make it. There are rare instances where nearly all puppies from a good litter become field champions and go on to produce good puppies as well. Dig deep into these and you'll see.
Like this one.
and this one.
and while we're at it throw this good girl in for good measure.
The easiest thing to do is call Mary and ask who the best bitch is that you could buy a puppy off of.