Enough to spend $1.9 million on them?

That's how much a Tibetan mastiff was sold for in 2014.

Dog breeding is a complicated and sometimes murky world, but for the people involved, it's a lifelong obsession.

So why are pedigree dogs so expensive?

And what is it that makes some cost so much more than others?

This is Crufts.

Every year, over 21,000 dogs from 43 countries compete, and it's here that you can see some of the world's most expensive dogs.

Akitas, chow chows, Löwchens, and Samoyeds.

I've had Samoyeds for over 30 years, and I couldn't have any other breed.

There is nothing quite like them.

They are the most joyous dogs you would like to have, naughty, but very nice to have.

They have some interesting habits and traits, such as barking and digging, but you can stop them doing it if you do it at an early age.

With all the coat that they've got, they do need an awful lot of grooming.

We recommend 10 minutes a day keeps on top of the coat, but they do shed their coat once or twice a year.

NARRATOR: A pedigree is proof of a dog's lineage.

It's a family tree showing the parents, grandparents and even great-grandparents of each registered dog.

Having healthy parents that've competed in shows or trials can drastically increase the price of the dog, and this lineage is taken very seriously.

Some owners even get their dogs DNA tested to guarantee they are purebred.

Once you've paid the $10,000 for a pedigree purebred dog, they can be costly to look after.

Vet bills for purebred dogs can be higher, and certain breeds have much higher chances of some conditions.

Samoyeds, for example, can have problems much higher chances of some conditions, and even hip dysplasia.

Breeders will also invest in pedigree pets for sponsorship deals and prize money at international shows, driving their demand and price up even further.

Dogs with certain temperaments, builds, or features that are likely to do better at shows can cost far more, and if you have a male pedigree dog, there's real money to be made as champion dogs can have stud fees of over $1,000.

The heritage of each breed plays a huge part too.

A lot of people are interested in history of breeds, and it has a lot to do with the way that the breeds will actually behave.

If you have a dog that has always rounded up sheep, you tend to have a dog that will round up the family.

So there are some instincts that we've bred into dogs over the generations, which tend to come out now.

So if you have a dog that's always bred to be a companion, something like the Pekingese or some of the other toy breeds, then they will naturally make good companions because that's what they were bred for.

Breeding can also save vulnerable breeds of dog.

The Löwchen, a tiny breed worth up to $10,000, has been around since about 1442, but by 1944, they were extremely rare.

Breeder Madame Bennert brought them back from the brink of extinction, and in 1971, the Löwchen Club of America was formed.

There are understandably less of them around though, which means they can be more expensive than other breeds.

But at the same time as saving some breeds, the owners market can put them in jeopardy.

It was reported in 2018 that thousands of Tibetan mastiffs were being abandoned in China.

Once the most sought-after dogs in the world, costing up to $1.9 million and prized for their rarity and status, there was a complete collapse in demand.

The dogs were suddenly worthless, and many were even slaughtered for their meat or fur.

If a breed becomes very popular, then breeders can charge a lot more, and there are obviously a lot who care lots about their animals and they're breeding them to the best of their abilities.

But if they're unable to get enough puppies out there for the demand, then that's where the unscrupulous breeders will come in.

And unfortunately they can make an awful lot of money, possibly poor welfare, for the bitches and the puppies, and we see this, sadly, at the RSPCA.

The inspectorate do come across puppy farms, and it's pretty horrific, but they can make an awful lot of money out of it.

These sudden booms in popularity for certain species spike the price, and what's fashionable or photogenic plays a big part.

Instagram is flooded with Tibetan mastiffs, huskies, Shiba Inus, chow chows, and Akitas, often bred to accentuate their cute features.

I think a lot of the flat-faced dogs, the ones with no nose, the brachycephalics, they are very cute, so they're seen on all the social media, and stars and all the rest of 'em got these dogs, and so people want to have them as well.

There's no doubt that we're seeing more and more of them.

But they have been bred to such an extreme that they have so many things that I could tell you about wrong with their airways, their tongues are too big, their soft palates are too big.

It's the extremes of breeding that we can see some things that some of these animals will die.

Regardless of what you think of pedigree dogs, demand and price is growing with a 7% rise.