You have chosen a very popular breed, so lots of litters to choose from, if there is only one left, ring up about another litter instead. If you buy a dog from strong working lines, it may well be a strong working dog, which is fine if you want to work it but can be a nightmare as a pet dog.

As regards sex I find bitches more bidable than dogs, though others may disagree.

I'm sure other can give you info as to what to look out for health wise.