If you're an investor, you've witnessed something truly unprecedented over the past five weeks. The benchmark S&P 500 has lost approximately 34% just since Feb. 19, 2020, with the stock market nosediving to its quickest bear market in history -- it took just 16 trading sessions to push from recent highs to a greater than 20% decline.

Furthermore, there's virtually no certainty as to when we'll have an upper hand on the coronavirus disease 2019 (COVID-19). As testing has picked up, so have confirmed cases in the United States and around the globe. Stricter mitigation measures being put in place to "flatten the curve" and ensure our healthcare system doesn't become overwhelmed will come at a huge cost to the world's leading economy. In fact, one investment bank on Wall Street is calling for an almost unfathomable 24% decline in U.S. second-quarter gross domestic product.

Yet despite this overwhelmingly pessimistic forecast, there's solace in knowing that, over the long run, high-quality businesses tend to increase in value. Prior to COVID-19, there were 37 stock market corrections of at least 10% in the S&P 500 over a 70-year period. Each and every one of these downturns, no matter how long or steep, was eventually erased and put well into the rearview mirror by a bull-market rally. That, too, will eventually be the fate of the steepest sell-off in history.

Five one-hundred-dollar bills laid out neatly atop each other.

Image source: Getty Images.

Put in another context, this means that if you have cash to spare -- i.e., money you won't need to pay bills or reserve for emergencies -- now is the time to put it to work. And don't think you need a small fortune to be successful. If you have even $500 to spare, then these top stocks should be on your buy list right now.

McDonald's

Next to the oil stocks, perhaps no industry has been clobbered more thoroughly than restaurants. Whereas most sit-in dining chains are experiencing a shock like never before, well-branded fast-casual chains look like a bargain. That's why it's time to consider taking that $500 and scooping up shares of the Golden Arches, McDonald's (NYSE:MCD).

Prior to coronavirus spreading around the globe, McDonald's was coming off its strongest year in more than a decade. It delivered more than $100 billion in systemwide sales and 5.9% comparable-store sales growth in 2019 -- and the Velocity Growth Plan is to thank. Introduced in March 2017, McDonald's strategy focused on regaining previous customers with higher-quality products, retaining existing customers, and pulling in new customers from other businesses through add-ons, such as coffee and snacks. When combined with digital, mobile, and delivery initiatives, this strategy has worked wonders.

Right now, investors can buy into McDonald's for about 15 times next year's projected profits and roughly 12 times next year's cash flow. Both figures represent levels we haven't seen since 2012.

Berkshire Hathaway CEO Warren Buffett at his company's annual shareholder meeting.

Image source: The Motley Fool.

Berkshire Hathaway

A great way to gain instant diversification without having a boatload of capital to invest is to buy Berkshire Hathaway (NYSE:BRK.A) (NYSE:BRK.B) stock. In this instance, I'm referring to the "B Class" shares (BRK.B), since the A Class shares go for around $240,000 each.

Buying into Berkshire Hathaway sort of makes its CEO, Warren Buffett, your portfolio manager. That's because Berkshire has acquired around five dozen businesses over the years from a variety of industries and sectors, and Buffett controls more than $150 billion in assets under management. Berkshire currently holds 52 securities, with banks, information technology, and consumer staples being the Oracle of Omaha's favorite sectors. You'll note that all three of these sectors are cyclical, meaning Buffett tends to do best when the U.S. economy is growing.

In case you need any more encouragement, understand that while the S&P 500 has returned close to 20,000%, inclusive of dividends, over the last 55 years, Berkshire Hathaway's per-share market value has increased by (drum roll) more than 2,700,000% over this same period. That's not a typo, and it's all the more reason you should ride Buffett's coattails to big gains.

A small pyramid of tobacco cigarettes that's lying on a thin bed of dried tobacco.

Image source: Getty Images.

Philip Morris International

If you're a socially responsible investor, look away now! But if you're willing to consider putting a top-tier tobacco company into your portfolio, then take a gander at Philip Morris International (NYSE:PM).

While there's no denying that some developed countries are making life difficult for tobacco producers, Philip Morris has a few tricks up its sleeve. For one, it doesn't operate in the U.S., but it does have a presence in more than 180 countries worldwide. Thus, if developed nations become stricter with packaging or advertising, there are more than enough emerging markets in which Philip Morris can offset this weakness.

Additionally, tobacco companies like Philip Morris have little issue passing along price hikes to negate lower shipment volumes, and they are unlikely to see much in the way of sales loss during the coronavirus crisis due to the addictive nature of nicotine.

As one added bonus, Philip Morris recently launched its heated tobacco system, IQOS, in a number of new markets. IQOS should help to drive growth beyond just traditional tobacco sales. At only 10 times next year's profit forecast and sporting a nearly 8% yield, this stock looks to be a bargain.

A cloud in the middle of a data center that's connected to multiple wireless devices.

Image source: Getty Images.

New Relic

Although there's certainly a focus on value as the market plunges, it's important for investors to not forget about long-run, high-growth tech trends. That's why mid-cap software-as-a-service provider New Relic (NYSE:NEWR) should be on investors' buy lists.

New Relic was already limping a bit heading into 2020 after a disappointing earnings report last summer led to a lower-than-expected dollar-based net expansion rate, or DBNE. The DBNE is New Relic's way of measuring existing customer spending from one period to the next. But the thing is, the quarter in question produced a DBNE of 109%, which is still impressive growth. In the company's two subsequent quarters, DBNE has stabilized at 112% and 109%, respectively.

Meanwhile, the percentage of sales derived from enterprise paid business accounts rose to 62% of total sales in the fiscal third quarter, up from 56% in the prior-year period. In other words, it's a subscription-based model that continues to tack on highly predictable cash flow. As businesses move into the cloud and away from brick-and-mortar stores, New Relic's tools will be relied on more than ever. That makes it a smart place to consider parking $500 right now.