How much is that doggy listed online? The one that may not exist?

Police, pet adoption advocates and defrauded pet owners are warning about online pet scams aimed at stealing thousands of dollars for a pet that may not arrive...

In Glen Cove, Catherine Masterson, 70, thought she had found a 2-year-old Neapolitan Mastiff, named Titan, in Colorado.

But Titan never showed.

Masterson had gone looking for a new purebred dog on a Facebook group after her previous longtime canine companion had died. She was quickly contacted by someone who said he was in North Carolina and offered to connect her with Titan for $3,000.

She said he wanted $1,500 up front and would only accept cash wire transfers. When her bank would only allow a limited amount to send by Zelle, he asked her to send him Apple gift cards.

"Not having done this, I was naive," Masterson told Newsday. "And I think he's legit. I'm not thinking scammer. You know, I'm naive about this. I was guilty of naivete."

The scam continued to the moment she thought her new dog was set for arrival. She became suspicious when she received messages asking for a $3,000 crate to transport the dog on an airplane. When she asked for photos and videos, she was sent photos looking like they were taken in a backyard claiming to be at the airport.

Masterson never talked to a live person and only communicated online or through text messages. She said her request to refund her $1,500 was never fulfilled.

Glen Cove police, who are investigating the fraud, said it has all the traits of a common scam, including asking for cash and gift cards.

"It looks like a scam," Glen Cove police Lt. John Nagle said. "She was trying to purchase the puppy online, and she had to pay multiple payments up front. She never saw these people in person, and when they finally asked for additional money to ship the dog, she realized she was being scammed."

Nassau County police said they have investigated two similar online pet scams this year.

A former Port Washington woman, Alissa Greenberg, 75, who now lives in Pleasantville, said she was scammed out of more than $2,000, from an alleged seller of puppies online asking for cash app payments and Apple gift cards for a Japanese Chin.

"Now I see a million red flags," Greenberg said. "I was distraught because I thought my puppy was stranded, but now I know it’s a total scam."

Police and experts said scammers may prey on vulnerable buyers online looking to adopt certain high-end breeds. Like many other scams, police said the organizations can be hard to track down and may originate overseas. International scammers may also use AI to communicate in English.

A spokeswoman for the American Kennel Club said those looking to adopt a dog should seek reputable adoption agencies.

"Unfortunately, online puppy scams have been on the rise for a while. Whatever way you decide to acquire a puppy, whether it be from a reputable breeder or rescue organization, potential puppy buyers need to be aware of the red flags that signal a scam is likely," said Brandi Munden, the kennel club’s vice president of communications.

"A lot of times, scammers use stock photos or steal photos and text from other sites. Search for the text in the listing to see if the seller copied and pasted it from another site," she said in an email. "If something seems too good to be true, it most likely is a scam."

John Asbury is a breaking news and general assignment reporter. He has been with Newsday since 2014 and previously worked at The Press-Enterprise in Riverside, California.