If you're considering the idea of adding a four-legged member to your family, you're likely picturing a lot of rainy-day snuggling and Instagrams that solicit "awwws" from your friends.

But there is one more practical thing to consider: the costs.

And by costs, we're not just referring to how much you'll pay to get the animal — there are plenty of other key expenses, from food and vet bills to petsitting.

Granted, every pet is different — and so is every budget. To get an idea of how much an owner should expect to shell out, we spoke to three animal lovers with different types of critters to see how one year of costs break down. Then we asked Elizabeth Sklaver, a CFP® with LearnVest Planning Services, to weigh in on their pet budgets.

Angel the Pug, Silver Spring, Md.

Karen Shakira Kali — along with her wife, Jenn, and their daughter, Doris — have a nine-year-old pug named Angel.

Although Angel eats premium kibble and fresh raw food, their total food expenses are fairly moderate. "It helps that having a small dog means she eats less because I do want to give her good food," says Kali, a 33-year-old urban planner. The cost for treats is even less — Angel is happy to snack on carrots, cucumbers and especially green beans.

Vet costs, however, aren't necessarily cheaper just because you're little. Angel takes several medications for arthritis, and like many pugs, she's on a regular eye medication — all of which amounts to about $550 a year.

"At least once a year, maybe twice, Angel eats something that she shouldn't," says Kali. Fortunately, emergency assistance calls to the Animal Poison Control hotline (normally $65 per call) are included in the $18 yearly fee that the family pays for the pup's tracking microchip.

The Kalis also spend $600 a year to have pet insurance, which covers 80 percent of their vet costs once they meet a $200 deductible. "I'm more of a 'we need to take the dog to the vet' person, and my wife is more of a 'let's wait and see' owner. Having pet insurance is a bit of a relief because it means that I can take the dog in without worrying too much about cost," says Kali.

The family gets a break on expenses in other ways, as well: They use recycled bags for cleanup, and Angel isn't really interested in toys. And, when they travel, Kali says that they're fortunate to have pug-loving friends who are willing to dog-sit, which is a big savings. "Although we do bring back presents, give gift cards and send special treats to our friends to show our thanks," says Kali.

What Elizabeth says: "The Kalis are very lucky to have friends that help with dog-sitting. I know from experience with my own two dogs that walking and sitting can be an expensive proposition, so make sure that you know the costs in your area, and budget appropriately. And remember: Even though you may not need help now, a move or a job change could make these services a necessity at some point during the life of your pet. The ASPCA estimates that the annual costs for a small dog are about $580 — and Angel's are nearly quadruple that. However, it's not surprising given that she's aging and has health issues. But I am surprised to see that their pet insurance covers so many of their vet expenses, because most affordable insurance policies ($30 to $50 a month) only cover catastrophes. For that reason, I wouldn't say having pet insurance is a necessity — rather, it depends on your personal preference."

Fred the English Spot Rabbit, Howell, Mich.

"I started volunteering at Great Lakes Rabbit Sanctuary in 2007, and Fred was one of the first bunnies I met," says Carrie Henderson. "I didn't plan to bring home a rabbit, but Fred had other ideas!"

Henderson later adopted Californian rabbit Kenzie as a companion for Fred. But the thing about having two rabbits, Henderson explains, is that the costs don't divide equally along bunny lines. "You'd think that it would cost double — in fact, it's just a little more than having one," she says, because they share things like a hutch, grooming supplies and toys.

The 48-year-old full-time student was also surprised that veterinary care for her rabbits costs much more than it did for the dogs she used to have, which only visited the vet once a year for checkups. By comparison, Fred spent two nights (and $1,000) in emergency care for a gastrointestinal problem known as stasis, and he's also developed dental spurs, which need to be fixed regularly at $300 per visit. Rabbits don't necessarily need more health care than other animals, but they are considered exotic pets, so not every veterinarian is able to treat them — and most who can charge more to do so.

Some other costs that are chipping away at Henderson's budget: litter and food. While hay only costs $150 a year, she estimates that her bill for fresh produce is around $1,000 annually. "Rabbits can't have regular litter because it's poisonous to them," she explains. "So I use a recycled wood pulp variety that costs $20 a bag, and I go through about three of them a month."

Of course, not everything related to caring for bunnies is costly. Their favorite toys are decidedly budget-friendly, like toilet-paper rolls stuffed with hay. And they don't require day care. "Rabbits are crepuscular, so they're most active in the morning and the evening," Henderson explains. "So when I'm up, so are they, and when I leave for school, they're settling in for naps. I don't have to worry that they'll be bored or miss me."

What Elizabeth says: "One thing that I often see with clients is under-budgeting for day-to-day pet expenses, such as animals destroying their bedding, or a medical emergency, like Fred's stasis. In accordance with the 50/20/30 rule, pet costs fall into the lifestyle choices category, so they should fold into the allotted 30 percent of your budget. The ASPCA estimates that a rabbit's care should cost $730 over the course of year, and Carrie's $3,525 total is a clear indication that you need to expect the unexpected — and leave room in your budget for it."

Bear the Domestic Short-Haired Cat, Paterson, N.J.

Linda Trepanier, an accountant, and her husband, Rob, have three cats: brothers Bear and Tux, who they've had about a year, and Raskol, who's lived with them for 11 years.

Bear was adopted from a friend whose cat had kittens, so it didn't cost anything to add him to the family. But, as any pet owner learns, the cost to acquire a pet is only a small fraction of the animal's lifetime expenses. Bear's vet costs, for instance, quickly skyrocketed to $279 this year, thanks to an eye scratch and then earmites.

But Trepanier says that spending money on the cats is never a source of contention in her household. "I read a book once about how to cut costs while unemployed," she says. "The chapter on pets was one sentence long: 'We know you won't scrimp on your pet, so save money elsewhere.' "

Her top recommendation for how to save? Cat furniture is particularly expensive, so she suggests looking in resale shops. "I even made a cat tree out of scraps of wood and old carpeting that lasted for years," she says.

Trepanier also recommends viewing cat food commercials with skepticism. "I don't buy rock-bottom-priced food," she says, "but you can find reasonably priced options that are nutritious and tasty." She adds that although most felines are reluctant to try new food, with patience, they'll probably come around.

And she has one big warning: "Do not scrimp on litter! It's worth the extra cost to get a good one that's scoopable, will control odors, and will hold up well if you don't clean the box every day."

There's also one interesting expense included in the toy category in this cat-loving home. "We spend $15 a month on wild seed to attract birds to our porch," she says. "Bear loves to watch them for hours!"

What Elizabeth says: "The ASPCA estimates the annual costs for a cat at $670 a year — and Bear is obviously more expensive than that. But I'm sure his costs overlap at least a little with the other two cats in this household.

Plus, it sounds like the Trepaniers have been very thoughtful about making decisions for their cats. Knowing that high-end kitty litter will be more cost effective than expensive food is a great tip. It really speaks to something many people overlook, which is that the "this or that" dilemma — knowing you have to choose where your money goes — isn't just about coffee versus a new outfit. It also applies to your pets."

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