How to: Work out how much your pet costs

REALITY BITES: How much are these doggies? Expensive - but cheaper than raising a child.
REALITY BITES: How much are these doggies? Expensive - but cheaper than raising a child.

How much is that doggy in the window?

His "waggly tail" needs surgical correction. He only eats the best chow. He needs to be microchipped, registered, groomed, clipped, spayed, de-fleaed, and sent to doggy day-care. Then there are collars, leads, a coat when it's cold, a snug kennel and a selection of toys.

On closer inspection, the little doggy's price tag reads anywhere between $10,000- $15,000.

Getting a pet is a big financial decision when you calculate the expenses over the lifespan of the animal. Not many people think about it in those terms, but perhaps they should.

"If we look at why animals are abandoned or surrendered...probably the biggest element would be cost," says SPCA national president Bob Kerridge.

The SPCA's intake of unwanted animals would probably make a good economic index. It spikes when times are hard.

"Quite often, sadly, the animal is down the list," Kerridge says.

Luckily the animal kingdom has provided us with a rich selection of companions that can match any price range.

We've worked out how much popular pets will cost you over the course of their lifetime- all the way from goldfish to giraffes.

Just for fun we've also compared the cost of each animal to the expense of raising a human child to age 18, which Inland Revenue pegged at $250,000 a few years ago.

$100 startup cost, $20 annual expenses, $300 lifetime cost over 10 years.

Buy a goldfish. Plonk it in a bowl. Feed it. Goldfish are low cost and low maintenance - the perfect entry-level pet.

While many are quickly sent down the porcelain chute to fishy heaven, goldfish actually live for 10 years when looked after properly.

A quick call to Four Seasons Pets confirms that yes, they do need flowing water unless you're prepared to change it every couple of days.

Filters start at $23 and the electricity cost is minimal. The only recurring cost is fish-food, dispensed a pinch at a time.

In fact, goldfish are so ridiculously cheap to run that you could have more than 1,000 fishy friends for the price of raising a single child.

$250 startup cost, $150 annual expenses, $1,150 lifetime cost over six years.

The cost of keeping a guinea pig is very low, says NZ Cavy Club treasurer Christa Krey.

"If it is kept in an outside run on grass, it can be supplemented with the household vegetable and fruit scraps, cost zero."

Hay for bedding and food is essential- $16 a year bought in bulk, she says. Pellets cost about $90 a year if you don't have other food sources.

A hutch will set you back about $200 and the pigs themselves are only about $10.

If they're sharing hutches and hay, you could care for 380 furry fluffballs for the price of a child.

$150 startup cost, $150 annual expenses, $1,650 lifetime cost over 10 years.

Budgerigars are going cheap (or should that be cheep?) on TradeMe for about $10-$20, and a 10kg sack of birdseed costs $32 at pet stores.

They're as inexpensive as guinea pigs but live a few extra years before falling off the perch, hence the higher lifetime cost.

Economies of scale by housing a flock of budgies sharing toys, grit and aviaries mean you could raise roughly 320 birds for the price of a kid.

$250 startup cost, $466 annual expenses, $7,250 lifetime cost over 15 years.

The average cat costs $466 a year, according to a report published last year by the Companion Animal Council (CAC).

That's a big step up from the smaller critters. It's probably because cats love to eat and they love to fight. Your average feline friend chows down on $275 of Whiskas a year, and chews through $125 for vet fees and healthcare.

The rest is a mix of kitty litter, toys, boarding fees and all the other accumulated expenses.

You can adopt a kitten from the SPCA for $150, which has already been microchipped and vaccinated. But it still needs to be desexed, which costs $60 - $100, and kitted out with a collar, bowl and other feline paraphernalia.

What's the kitten-to-kid expense ratio? A crazy cat lady with 34 moggies caterwauling and tearing up the furniture will come out roughly the same as if she had a single child.

$700 startup cost, $1,047 annual expenses, $13,250 lifetime cost over 12 years.

Canine companions are roughly twice as expensive as cats. There's the added cost of registration, which can be as much as $130 a year or more if the breed is classified as dangerous.

"When registration on dogs are due, there is a spike in dogs being surrendered," says the SPCA's Kerridge.

Like cats, healthcare and food are the big costs, but they're scaled up accordingly. CAC found that your average hound costs $1,047 a year, of which $465 goes towards tucker and $262 to the vet.

On top of that, there's a whole range of extra spending on grooming, boarding, clothing and more.

Start-up costs are higher too. Adopting a puppy costs $260, desexing is another couple of hundred, a kennel the same again and collars and leads are about $50.

You'd have to be barking mad, but you could spend a small fortune on 18 dogs and be no worse off financially then if you'd raised a child.

$6,000 startup cost, $3,000 annual expenses, $80,000 lifetime cost over 25 years

Surprisingly, the CAC report put the cost of a horse or pony lower than a dog, at $895 a year. calculated the conservative annual maintenance cost at $3,000 a few years back, and editor Robin Marshall says that figure is still accurate.

Marshall knows the costs of ownership better than most - she's just had the dentist in to see seven horses ($490), and paid $150 for sports massage therapy for two.

"I do believe if you can't afford the costs that go along with a horse - including unexpected vet costs - you should not have them," she says.

If you don't have land, grazing is a huge expense. It varies but can be $50 a week or more, which quickly becomes thousands over the course of a year.

Marshall notes that if your horse competes the costs skyrocket, with all the associated gear, travel, vehicles and entry fees.

For all of that, you can still have three horses trotting around and be financially better off than having a sprog.

Unknown startup cost, $5,000-$10,000 annual expenses, $250,000 lifetime cost over 25 years

Why bother with cats and dogs when you can own six-metre tall African monsters capable of kicking lions to death?

Perhaps that was NBR Rich-lister Alan Gibbs' line of thinking when he installed two giraffes on his massive Kaipara sculpture park

It's the pet for the man who has it all - specifically, all the money. The cost of buying and transporting a giraffe is skyhigh.

Then there's all the upkeep expenses - housing, industrial-strength fencing, and a really, really long leash.

Wellington Zoo's only male giraffe died two weeks ago and a replacement imported from the United States could cost as much as $100,000.

The zoo says each giraffe chews through about $100 worth of food a week and also needs heating to replicate the natural habitat.

Taking a wild guess, we'll say the cost of giraffe ownership works out at least on par with a child, and probably much more.