Having the ability to invest your extra savings is such a powerful and wonderful position for anyone to be in. Because the stock market is the greatest wealth-building tool out there, investing early and often with a long-term mindset will likely lead to life-changing returns given enough time. 

If you have $10,000 ready to put in the stock market, then consider these two industry-leading companies. By focusing intensely on their customers, both businesses have a long track record of success and are worthwhile stocks to consider now. 

A stock trader analyzing charts on screens.

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1. Costco

Let's first consider Costco Wholesale (NASDAQ:COST), the popular big-box retailer. Its 820 retail warehouses offer customers a wide assortment of merchandise and groceries at some of the lowest prices around. People must be members to shop at Costco, which is known for outstanding customer service and a treasure-hunt shopping experience. Shoppers often find attractive items they didn't expect. There are over 111 million Costco cardholders today, and the renewal rate of 91.3% in the U.S. and Canada showcases their stickiness. 

Net sales of $192 billion in fiscal 2021 (up 17.7% year over year) demonstrate the massive scale of this business. And this size is a competitive advantage because Costco can negotiate better prices with vendors who want to maintain relationships with the company. Savings are immediately passed on to shoppers, which keeps the flywheel going. Adding members is Costco's overarching goal as most of the company's profit comes from these high-margin fees. 

The customer value proposition of Costco was never more apparent than during the past 19 months. People wanted to tackle their entire shopping lists in one trip, stocking up on essentials like food and cleaning products. In the recent quarter, however, categories like jewelry, home furnishings, and sporting goods showed strength. Same-store sales (or comps) increased 17.5% in October after jumping 14.4% in the prior-year period. Even as we slowly move past the pandemic, Costco's business just keeps humming along. 

The stock trades for 42 times forward earnings, a multiple that isn't excessive considering what a high-quality company Costco is. Net income has grown 113% over the past five years, and I see no reason why it can't continue rising at a solid clip in the years ahead. Consumers will always demand a wide selection, low prices, and a great experience, trends that support Costco's business. 

Investing in Costco stock seems a sound financial decision. 

2. Starbucks

As the world's leading coffeehouse chain, Starbucks (NASDAQ:SBUX) has 33,833 locations around the globe and generated record revenue of $8.1 billion in the most recent quarter. What was once touted as a place to spend time away from the home or the office, Starbucks has now become a business that's able to serve customers their favorite coffee or food items anytime they want. Having a powerful brand that's recognized worldwide is what makes Starbucks truly special. 

In the most recent fiscal year, U.S. comps increased 21% while international comps were up 16%. Even during a tumultuous business climate for restaurants, Starbucks was still able to open 1,173 net new stores in fiscal 2021. The company's top-notch digital platform offers an attractive rewards program to its 24.8 million members in the U.S. and 17.9 million in China, along with a few other countries, allowing Starbucks to build connections with its most loyal customers while at the same time encouraging frequent visits. 

By 2030, Starbucks' management team believes that the company will have 55,000 stores in 100 different markets. That means there's still a sizable runway for expansion over the next decade. China, a country where Starbucks opened 654 net new stores last fiscal year, will undoubtedly be a major part of this expansion.

Starbucks shares are currently trading at a forward price-to-earnings ratio of 33, not exactly a bargain, but still attractive given the type of business it has. Sure, its sells a premium product, but even then I'd argue that the strength of the brand, coupled with the nature of repeat purchases by consumers, also makes this a consumer staple. People all over the world love their caffeine. This won't change anytime soon. 

In addition to Costco, scooping up shares in Starbucks looks like a great investment. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.