If you can answer ANY of these questions, that would be great. You don't need to answer them all obviously!!

Would you suggest one?
How expensive are they to own?
How much are they to buy as pups?
Are they good with children?
Do they need company throughout the day?
How much exercise do they need?

Talking from personal experience I would definitely suggest a newfie. Though they can be difficult as a pup to train in the beginning they do learn fast. They are very sweet, gentle, loyal and even though they are very large unlike most large breeds they know their size. They are good guard dogs as well, they are very good at sensing danger and will stand between you and danger and their deep bark can be intimidating.

They are like any other puppy when it comes to expense. You have to get all the regular shots and check ups. The only thing is they require a lot of food up to 6 cups a day when they hit 5-6 months old, but after 6 months you can ween them down to about 3-4 cup (same as a lab). If by chance you did have to go to the vet and they use anesthesia for what ever reason the breed is big so it would require more anesthesia which would show on the bill.

pets question and answers,www.5d2d.com

In the north east part of the country they range from $ 1,200 - $ 2,500 depending on color and if you want a show dog as the breeders call it. The black and brown color are generally cheaper the landseer (white or gray and black) usually cost more. If you come across a cheaper breeder I would not suggest getting a pup from them. Make sure they breeder has all the lineage paper work. You know you have a good breeder if they tell you to bring the dog back to them if you don't want him because it shows they care about their dogs.

They are very, very good with children. My newf will play with my niece who is a little over a year old and he will just lay down next to her and lets her do what she wants, I wouldn't worry about him hurting her but the other way around.

It is very important to give any dog as much company as possable especially during the puppy stage but if you work normal hours they are fine just give them some exercise when you get back from work because they tend to get lazy and overweight with out exercise.

pets question and answers,www.5d2d.com

As a puppy do not walk them too far at max half mile because they are so young their joints are sill developing you can hurt them in the long run. As the pup gets older go further. When they are grown they will be healthy and happy with a mile in the morning and one before dinner or about two miles a day how ever you wanted to do it.

In the end just be sure you want and plan to keep the newfie because a lot of people don't know how big this breed is until they have it and bail out and bring them to a shelter which this breed becomes very attached to their owners and have a very hard time warming up to a new family if they get a new family. Do a lot of research.

OK a little long but hope it help with your choice. I have had all different types of breeds and I wouldn't get anything but a newfie now.

Because of their size, they are expensive to keep: they eat more, need bigger collars and harnesses, bigger crates and beds, their vet bills are higher.

They are expensive as pups; in NE US, $ 1500 - $ 2500 is not uncommon for a well-bred pup from good stock. pets question and answers,www.5d2d.com

Newfs as a breed are natural born babysitters.

Newfs are pretty mellow; if they learn your schedule and know when to expect you, they can probably cope. An outside pen, safely away from your property line, might be a good plan. It depends on your family's circumstances.

They aren't boundlessly energetic, but they will benefit from an hour's walk or a swim each day.

They are very trainable and will try to do anything you want. It can be difficult to swim with them; they think humans are incompetent in the water and will rescue you whether you need it or not.:)

Huge drooling black calm dog if well bred should be fine with children and calm.
Price depends on breeder, area of country and quality.
With such a large breed I would definitely go and see the parents even with my 50 years of dog experience. That is a lot of dog for someone to handle and you want a sane line that you really like.
With such a large breed I would want Hip x rays done on both sire and dam, I would look into things like osteocondritis desicans and make sure it is not in the breed and if it is I would want to know who in the pedigree may have had it, same thing with patellas. That is a lot of dog and it would be foolish to have to pay for surgery to correct a large problem because you wanted to save a little money up front when buying the dog. pets question and answers,www.5d2d.com
Why not join a Newfoundland yahoo group or two and read through what people in the breed are saying?
As far as company the dog may be fine if it is sane without day time company.
Also DO NOT spay or Neuter a dog that size until it is over 2 years old.