PHOENIX -- Julia Gessner takes her little white puff everywhere.

So when Dillon had a hard time walking, Gessner turned to the people who'd taken care of him since he was a puppy.

She thought her Banfield plan would cover his hurt leg.

"I definitely thought it was an insurance policy, like people. I thought it was going to cover him if he ever were hurt," Gessner said.

The policy didn't cover Dillon's leg pain because it was actually a wellness plan, which differs from pet insurance.

"Basically, that provides wellness, vaccinations, screening tests, spaying and neutering. Basically things designed to help keep the animal healthy," said Dr. Mindy Fontius of Alta Vista Veterinary Hospital.

One customer told 5 Investigates that she loves the wellness plan because it helps her budget for regular expenses.

Wellness plans are available through veterinarians or clinics like Banfield.

But for something to help with major expenses, like when a pet is hit by a car or swallows poison, owners need pet insurance.

"[We've] certainly had cases where it's been a lifesaver for the people," Fontius said.

Lauren Blumber said it would have saved her friend thousands of dollars.

"We do it for the family, the baby, everyone, so why not for the dog? We consider them an essential part of our family," Blumber said.

Pet insurance covers everything from accidents to prescriptions to long-term care, but many don't cover pre-existing conditions.

"Sometimes we run into problems with the companies not necessarily disclosing every -- or providing a list of what would be excluded," Fontius said.

The cost of availability of insurance also depends on the pet's age, breed and health status.

The state of Arizona tracks only three pet insurance companies, but doesn't endorse any of them.

"Certainly, do your research and compare," Fontius said.

5 Investigates spoke with a Banfield veterinarian who said it's a good idea to have both pet insurance and a wellness plan.

He said that since pets age faster than people, taking a pet to the vet every six months is like a person going to the doctor every two or three years.

Other vets agree. "Meaning you're going to take them in once or twice a year, you're going to get all the vaccines, you're going to get all the screening tests, you're going to get all the suggested stuff, then a wellness plan might be a better way to go," Fontius said.

Wellness plans start at about $15 a month, while pet insurance for accidents starts at about $10 a month.

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