Charlie Munger has a net worth of $2.5 billion, according to The Real-Time Billionaires List from Forbes. The 99-year-old executive at Berkshire Hathaway (BRK.A 0.12%) (BRK.B -0.01%) has been Warren Buffett's right-hand man for many decades. But if there's one stock they've disagreed on, it's club retailer Costco Wholesale (COST 1.05%).

In early 2023, Munger said: "I love everything about Costco. I'm a total addict, and I'm never going to sell a share." Indeed, Costco is one of only three stocks that the famed investor owns directly. His ownership stake in the retailer is valued at close to $100 million, as of this writing.

Despite Munger's vow to never sell his shares, Buffett sold all of Berkshire Hathaway's shares of Costco in 2020. It's an ongoing source of friendly joking between the two. But considering Costco stock is up over 50% in the last three years, it seems Munger is getting the last laugh.

Munger's extreme affection for Costco is based on his love for the business model. It's a business model that he claims The Home Depot (HD 1.13%) directly copied on its way to delivering world-class investment returns. And Munger says that another growth stock is copying the exact same playbook today, making it one of the best, current investment opportunities in the stock market.

What is Costco's playbook exactly?

On Oct. 29, Munger made a somewhat rare public appearance, this time for the Acquired podcast. A wide range of topics were covered during the hour-long conversation, including discussing what he loves about Costco.

In short, Costco seeks to deliver exceptional value for its customers only in areas that can support high sales volume. Only operating in select areas keeps sales volume high and occupancy costs low. In this way, the company can pass on low prices to customers, who return the favor with loyalty.

Sol Price was an American businessman and is known as the father of the warehouse store model. His company Price Club ultimately merged with Costco. Price freely shared the strategy with other entrepreneurs. And on the Acquired podcast, Munger said that The Home Depot copied Costco's model in the home-improvement space.

The comparison is an apt one. The average Costco warehouse is 147,000 square feet whereas the average Home Depot has 128,000 square feet, if you include the outdoor garden area. Moreover, Home Depot has high inventory turnover, just like Costco.

Over the last 30 years, both Costco stock and The Home Depot stock have turned their shared business model into market-crushing stock returns, as the chart shows. And that's why Munger's latest idea is so important to look into.

HD Total Return Level Chart

HD Total Return Level data by YCharts

Munger's current growth-stock idea

The podcast hosts asked Munger directly if there were any new opportunities to copy Costco. Munger didn't hesitate to bring up Floor & Decor (FND 2.56%), a relative newcomer in the home-improvement space.

In 2018, Floor & Decor had just 100 locations. As of the second quarter of 2023, the company had 203 locations. And by 2030, it could have as many as 500 warehouse-style stores around the U.S.

For Floor & Decor, it doesn't aim to be as big as Home Depot with its more than 2,300 locations -- 500 will be enough for its niche product offering. The company isn't trying to sell everything. It mostly sells what you'd expect: flooring, things for installing flooring, and related home decor. That's a limited product offering, but it's a great idea.

The Home Depot and Lowe's offer the same products as Floor & Decor, but only in a couple of aisles. Likewise, smaller flooring stores have similar products as well. But Floor & Decor's warehouses average 78,000 square feet, giving it a much larger selection of products for customers and contractors to browse up close and personal.

The strategy of rolling up the flooring space is working. In 2022, Floor & Decor achieved its 14th consecutive year of same-store sales growth, showing that this concept resonates with customers. In the first half of 2023, same-store sales were admittedly down 4.7% from the comparable period of 2022. But Home Depot and Lowe's are seeing the same thing -- it's not just a Floor & Decor problem.

By opening around 300 new stores and further increasing same-store sales, Floor & Decor should see impressive revenue growth through 2030. And importantly for investors today, the stock trades at a below-average price-to-sales valuation of just 2.

FND PS Ratio Chart

FND PS Ratio data by YCharts

Not that he needs my approval, but I agree with Charlie Munger that Floor & Decor stock is a great investment opportunity right now. This business model has produced market-beating returns before, and it can keep it going through at least 2030. Therefore, if you haven't taken time to look at this company yet, now is a great time to do so.