
Hi Guest,
I think a lot depends on the breed of dog - some breeds are not great with youngsters around (although a lot depends on the parents ability to supervise) and may not have been born to a family environment so breeders could be naturally anxious.
Re the staying in a flat - while ideally most dogs are easier to house train if they have access to a garden, personally I don't think it is an *absolute* essential. I know people who live in flats and walk their dogs religiously three times a day in all weathers. Some folks with gardens only let the dog out to relieve itself if it is wet, windy, any month with an "r" in it

There are many things for breeders to consider when homing puppies and while all responsible and caring breeders have to put the puppy's needs as a priority, I think many are prepared to judge individual cases on merit :) The best advice to give you is be COMPLETELY honest with information requested of you and if you find that your preferred breed is difficult to obtain from a respected breeder at present be prepared to wait until your children are a little older.
Good luck, HTH,
regards Teri ;)