Ray Kroc was selling milkshake mixers when he decided to switch careers and convince the McDonald brothers to let him franchise their restaurant. He was 52. "Late-career job changes have become more common over the past several decades at the same time that working longer has become more necessary," concludes a study by the Center for Retirement Research at Boston College. "The rise in job-changing appears to be largely voluntary, with workers likely moving to jobs that they consider better." Marsha Lindsey is one of those people. She retired from a career as a corporate lobbyist in Dallas and made a hard left turn. At the age of 54, she opened Lucky Dog Barkery in a trendy shopping center. "My next door neighbor was upset, 'They're moving a dog store over here!'" she said. But her neighbors soon changed their minds.

Marsha Lindsey opened up Lucky Dog Barkery at age 54.

The Lucky Dog Barkery has been called the Whole Foods for dogs. It's filled with high-end pet food — bison, sardines, turkey — plus dog toys and pet clothing (more on that in a moment). Customers have been lapping it up for 12 years now. The average customer spends $65, and the store averages 90-100 sales a day. "We've got good quality people coming through the door," Lindsey said, and that has boosted traffic to the stores around her. Lindsey opened the story even though she knew nothing about retail. "My husband said the most I knew about retail was that I was on the wrong side of the cash register," she joked. But after Lindsey left her corporate job, a friend suggested she open a store for dogs. "I was doing consulting, found myself dressed up in airports, it wasn't much fun." But a dog store? "We've always had dogs, love dogs, but I'd never really dreamed of owning a retail store," she said. Lindsey did some research and convinced herself to move forward. "It's a very strong industry; it survives recessions." She's right. The pet food market is projected to grow from $24.6 billion last year to $30 billion in 2022, and natural pet food makes up over 25 percent of the market.

Start-up costs: $200,000

Lindsey started Lucky Dog Barkery with $200,000 that she "cobbled together" by pulling some money out of her retirement and getting a loan on her car. Her financial advisor disapproved. "He thought that I had maybe lost my mind." But the store was an instant hit when doors opened in late 2005. "I had customers that literally would look in a box that I hadn't even unpacked and wanted to buy things, and I'm like, 'Well, I don't have this priced yet.'" One reason Lindsey may have succeeded so quickly is because she was more focused on the look and feel of the store rather than on how much money was in the cash register. She designed a shopping experience that harkens back to an old-fashioned hardware store. Dog toys are organized in old nail bins that move on wheels. There's an old Coke machine from the 1950s. She wanted to recreate the feeling she used to have when she visited her uncle's all-in-one gas station/post office/feed store in the small Oklahoma town where she grew up. "When I would go back there I just felt at home. It was just the center of everything."

Lucky Dog Barkery in Dallas, Texas

From $350,000 to $1.6 million

How well has her dream worked out? First full-year revenues for Lucky Dog Barkery in 2006 were $350,000. "Last year we did $1.6 million." Lindsey has taken no outside investment. "I think we lucked out in that we were successful quickly." She credits hiring a small staff that really knew the products, and her own work getting to know the manufacturers. "What we try to do is teach people how to read an ingredient panel," she said. "There's a lot of really poor products out there." She's learned some tough lessons about managing inventory, and she's also learned more than she cared to about freezers — "they are expensive little things."

A different business plan

Lindsey has no desire to franchise the store, because she believes part of her success is that customers regularly see her behind the register. "I was always under the impression that small businesses sometimes don't make it because they're under-capitalized," she explained, "and a friend of mine who is in banking for small businesses said, 'No, it's when the owner gets too far away from the business.'" Lucky Dog Barkery also doesn't have an online store or do mass email "deals" because it hasn't been worth it. "We get much better results with things on Instagram and Facebook and then taking care of them when they come in the door so they tell other people about us."

Lucky Dog Barkery sells high-end, organic dog food as well as dog clothing and accessories.

No cats please

In the beginning, Lucky Dog Barkery also carried a few cat products, but that is no longer the case. "I had a cat customer come in that was not happy with the amount of inventory I had, even though I thought I had quite a bit," Lindsey said. "She sort of yelled at me. ... That's when I said, 'Ya know what? We're just going to focus on dogs.'"

More pajamas, please?

Sometimes a hit product catches Lindsey by surprise. "I had people asking for dog pajamas, and I thought, 'Really?'" she said with a grimace. "I said, 'Let me tell you, if you ever come into this store, and there are pajamas hanging in here, you know I've sold the store.'" Still, someone convinced her to give the pajamas a chance. "We sold through two orders and had a waiting list, and that was the 'Aha!' moment." There have been other "Aha!" moments: The average age of her customers is getting younger, men have become as interested as women in shopping for their pets, and pets are increasingly being treated as part of the family. "Some dogs probably eat better than the owners," she joked. "The other little tidbit is the smaller the dog, the more they tend to spend."

Lucky Dog Barkery made $1.6 million in revenue in 2016.

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