The stock market has taken investors on quite a roller-coaster ride lately, and I don't think the turbulence will be over anytime soon. Until we get some real clarity on when the economy might reopen and how deep the recession will be, volatility seems like the new normal.

While nobody can predict where the stock market will go in the near term, there has been no shortage of opportunities for long-term investors to buy excellent companies at rock-bottom prices. I've done quite a bit of buying during the market downturn, and here are two companies I'm particularly excited about that I recently added to my portfolio.

Person pushing a buy button on a keyboard.

Image source: Getty Images.

This robotics company has barely scratched the surface of its potential

Stocks that specialize in products that people don't really need have mostly been hammered, and iRobot (NASDAQ:IRBT), maker of the Roomba vacuum-cleaning robots and other robotic products, is no exception. And while the stock has rebounded somewhat since its March lows, it's still trading for less than half of its 52-week high.

iRobot's revenue will certainly take a dive. In a business update issued on March 23, the company said that it anticipates first-quarter revenue in the $175 million to $185 million range, which at the midpoint would be a decline of about 25% from the first quarter of 2019.

However, the company has a rock-solid balance sheet with more than $250 million in cash and no debt, which should allow it to make it through the recession just fine. And the long-term opportunity is just as compelling as ever.

The company sees an immediately addressable market opportunity to grow its Roomba usage by 150% and a longer-term opportunity to get its vacuums in 128 million U.S. households. (Currently, Roombas are owned by about 16 million households.) And that doesn't even take into account the potential in international markets, the company's Braava robotic mops, the Terra robotic lawnmower planned for a large-scale launch in 2021, or other future robotic home products.

This REIT should be just fine in the long run

I've been watching net-lease real estate investment trust STORE Capital (NYSE:STOR) for some time now, but since I have a large position in similar REIT Realty Income in my portfolio, I've been hesitant to pull the trigger. However, the stock recently became too cheap to ignore.

STORE (stands for Single Tenant Operational Real Estate) specializes in properties in the retail and service industries. Many are "essential" businesses like convenience stores and drug stores. But more than one-fourth of the portfolio is occupied by restaurants, movie theaters, gyms, and family entertainment centers. Worries about this part of the portfolio have scared investors.

However, I'm not worried about the company from a long-term perspective, and for good reason. With $700 million in liquidity, STORE should get through the tough times just fine, even if some tenants close locations or miss rent payments. And with the CARES Act providing funds to businesses of all sizes, I'm optimistic that the vast majority of STORE's tenants will be OK.

STORE Capital issued an update to investors in mid-March, emphasizing that its dividend is one of the safest in its peer group and stating that many of the company's management team had recently purchased shares themselves. The company has a dividend yield of 8.6% and an excellent long-term business model, so I'm confident that I'll be very glad I hit the buy button during this bear market.

Invest for the long term

I mentioned this in the introduction, but it's important to emphasize that I'm not saying that these stocks have hit their bear-market bottom yet or will rebound to their previous highs quickly. I expect both of them (and most other stocks for that matter) to be rather turbulent while the COVID-19 pandemic plays out.

However, both of these companies have long-term growth potential and are trading for extremely attractive valuations if you measure your investment returns in decades, not months or years. Investors should keep this in mind before considering either of these companies.