Even after a couple of good days for stocks, the S&P 500 is still down almost 26% since late February, wiping out trillions of dollars in wealth as the world faces the biggest health crisis and economic shock in decades. Many stocks are down far more, and depending on how bad -- and how protracted -- the economic downturn lasts, the worst could be yet to come. 

And while there could be more pain ahead, history is a clear guide, that people who take advantage of big market crashes like this to buy are the ones who profit in the long term. And while in the past the scales were decidedly tipped to the favor of whoever had the most money, competition and technology have become great equalizers, and people with even a small amount of money can now put it to work in ways that were impossible even a couple of years ago.

Planting money to make it grow.

Image source: Getty Images.

Not only have brokerage trading fees become a thing of the past, but several online brokers also make it possible to buy fractional shares. That means you can now invest in a company whose shares cost $500 each, even if you don't have $500 to invest. Even if you only have a little money set aside, say $100, you can now invest in even stocks that may have been out of your reach in the past. 

Here are three of my top ideas: Brookfield Asset Management (BN 0.65%)MercadoLibre (MELI 1.09%) and First Solar (FSLR 2.70%). Keep reading to learn why even a small amount of money invested in these three stocks should reward you with big gains over the long term.

Do this first

With the stock market down so far, it's great if your instinct is to act opportunistically to buy right now. Market crashes are the best time to buy. But that's only true if you've made sure to protect your personal downside first. If you don't have any substantial savings to help make ends meet if you lose work or otherwise have no income, take that $100 (or however much you have) and stick it in a savings account. You may not earn much yield, but you won't run the risk of seeing $100 you might need in a month, turn into $50 just because the stock market keeps falling during the current downturn. 

Buy this business built to take advantage of downturns

At this writing, shares of Brookfield have lost more than 30% of their value during the coronavirus crash, which just doesn't jibe with the reality of its business. Brookfield is a global giant in alternative asset management, and its share price has become disconnected from the value of the earnings from its investment management business and the cash flows its subsidiaries generate. 

But here's the big one: Brookfield is an ideal stock to own during market crashes. The company has a long track record as a successful opportunistic investor, taking advantage of market downturns to buy high-quality assets at fire-sale prices. I expect we will see the company, or one or more of its subsidiaries, do exactly that at some point this year. 

CEO Bruce Flatt reiterated that recently in a letter to investors, going so far as to point out that Brookfield's own stock represented a highly undervalued asset at recent prices, which are almost 40% below the peak in February. 

A balance sheet built for now, a business built for years of growth

Latin America is facing the same health and economic impacts from coronavirus as is the U.S. And in some ways it could be worse, with weaker and more limited access to adequate healthcare, and economies that are more susceptible to downturn. That's a big reason why MercadoLibre stock has fallen far more than the overall market. Its near-term results could really get ugly if consumer spending in its major markets falls off. 

But with a fortress of a balance sheet that includes almost $3 billion in cash versus $800 million in debt, and a business that's generated positive cash flows every year since going public, investors can rest easy that the company can survive the downturn just fine. 

MELI Cash and Short Term Investments (Quarterly) Chart

MELI Cash and Short Term Investments (Quarterly) data by YCharts

And once the world gets back to normal and economic activity rebounds, no company is as well-positioned to grow in Latin America than MercadoLibre. Moreover, its status as the e-commerce leader there could help it establish an even bigger lead over the competition even before life -- and the global economy -- returns to normal. 

Another balance sheet behemoth with gigantic growth prospects

First Solar investors can tell you from experience that renewable energy stocks can be very volatile. This isn't the first time that the company's shares have lost more than 40% of their value multiple times over the past half-decade: 

FSLR Chart

FSLR data by YCharts

But as the chart above also shows, it has also proved to be a very profitable investment from those low points, as both demand for renewable energy increases, and sentiment shifts back in favor or solar stocks. 

For First Solar, this often results in a disconnect between the company's stock price, and fair value for its business. For instance a recent market capitalization -- the value of the company's shares -- was $3.6 billion, for a company with $1.8 billion in net cash. In other words, the market only values First Solar's solar business at $1.8 billion today. 

And $1.8 billion is cheap for a company that's consistently generated more than $500 million in annual operating cash flows in the past (2019 was an aberration due to some major spending to convert its plants to a new product). 

Yes, First Solar is a very volatile stock in a volatile industry. But its rock-solid balance sheet backstops one of the best utility-scale solar panel manufacturing businesses in the world. It's trading at fire sale prices right now. 

Putting small amounts of money to work has never been easier

At recent prices, buying just one share of each of these three companies would cost over $563. In the past, that -- along with at least $5 per trade or more in fees -- made it impossible for people working with small amounts of money to invest. 

But between the elimination of trading fees and many brokers now allowing fractional investments, the playing field has been leveled. If you've got a spare $100 or other small amount of money you'd like to invest, now's the time to take advantage of the coronavirus market crash. The three stocks above look like perfect opportunities, and if you're willing to hold through the downturn, for at least a few years and ideally much longer, you could see your small investment turn into something much bigger.