There are a few things to look for in stocks that could deliver excellent long-term performance. For starters, you should look for strong profitability, financial stability, a history of strong but responsible growth, and the potential to grow much more. With that in mind, here are two stocks that I think could deliver market-beating returns for years to come.

A young and growing self-storage brand

The self-storage business is an attractive one from a long-term perspective. Storage facilities tend to have lower operating costs and turnover expenses than other property types, meaning that profit margins are high. And demand for storage has accelerated rapidly, as Americans have a growing need for space to keep their belongings.

Stacks of coins with growing plants in the middle of each. Meant to symbolize money growing.

Image source: Getty Images.

There are several smart ways to invest in self-storage, such as industry leader Public Storage, which I own and have written about before. However, one self-storage REIT with tons of room to grow is Life Storage (NYSE:LSI). If you haven't heard of Life Storage, it's possibly because until August 2016, the company was known as Sovran Self Storage, operating under its Uncle Bob's Self Storage brand. Throughout 2017, all of the company's storage facilities will be rebranded under the Life Storage brand name, and so far the market reaction indicates that it was a good change.

Life Storage currently has about 650 storage facilities in 29 states, with the majority concentrated along the Eastern U.S. and Texas. The company has grown rapidly, especially in recent years -- in fact, Life Storage added more than 100 facilities in 2016 alone, and has done a great job of increasing its occupancy and rental income over the past few years.

Charts of Life Storage occupancy and rent growth.

Image source: Life Storage investor presentation.

Since 2011, Life Storage has grown its same-store revenue at an impressive annualized rate of 6.2% while expenses have only grown at about a third of that rate. This is a big reason why the company's FFO per share has more than doubled since then, and the dividend has increased by about $2.00 per share.

With a strong balance sheet, investment-grade (Baa2/BBB) credit ratings, and enough financial flexibility to keep its growth momentum going, there's no reason to think that Life Storage won't keep these trends alive for years to come.

Strong profitability in a growing rental market

EdR Trust (NYSE:EDR), which stands for Education Realty, is one of the largest REITs focused on collegiate housing. As of this writing, the company owns or manages 86 student housing communities in 24 states. The company's properties are located extremely close to large universities, with the average property just 0.3 miles from campus.

There are several reasons to invest in collegiate housing. For starters, college enrollment has been steadily rising and is projected to continue to do so through at least 2024. The earnings gap between college graduates and non-graduates is the widest it's been in nearly 50 years, and public four-year institutions (where EdR's properties are concentrated) are growing faster than private and two-year colleges.

One reason I'm specifically including EdR in a discussion of stocks that can make you rich is that the company's properties are located on, or near, highly rated universities with above-average enrollment growth rates. In fact, 2016 was a rare year where overall college enrollment declined (mainly due to a big drop in for-profit college enrollment), but EdR's target universities still grew enrollment at a healthy rate. EdR's properties rent for more than those of its leading peer, American Campus Communities, and they operate at significantly higher profit margins. And in the six-year period through 2016, EdR has generated stronger revenue and NOI growth.

EdR versus ACC profitability metrics.

Image source: EdR investor presentation.

Another reason I like EdR is its two-sided investment strategy. The company actively acquires existing properties located in markets that match its core objectives. In 2017, the company plans to spend about $145 million on acquisitions.

In addition, EdR also grows by developing new properties from the ground up, which can create instant value for shareholders. There are currently development projects in the pipeline at Cornell University, University of Kentucky, Michigan State, and several other major institutions. In all, EdR expects to spend nearly $1 billion on developments through 2019. This is significant because not only do newly developed properties produce higher yields than acquired properties, but if they are built at a discount to their intrinsic value, instant value is created for shareholders. In fact, EdR estimates that the nearly $1 billion in developments will result in about $226 million of instant added value for shareholders.