It takes money to make money. Most people know the old adage is true. But it doesn't necessarily take a lot of money to make, well, a lot of money.

Even an initial investment of $3,000 can grow into a substantial sum over time. The trick is to find the right opportunities in which to invest. Buying stocks has proven to be a great way to generate huge long-term returns.

But which stocks are good candidates to make a lot of money without having a lot of money to invest? Investing $3,000 in these three stocks could make you a fortune over the next decade.

Smiling person lying on top of a pile of one dollar bills.

Image source: Getty Images.

1. Fastly: Leading on the edge

Here's a number to keep in mind: 75%. That's the percentage of internet applications that will be built by companies in the coming years instead of bought, according to market researcher International Data Corporation. It's also the percentage of data IDC expects will be processed at the edge of the cloud (the point where corporate networks connect with the cloud) by 2022. One company is uniquely poised to benefit from this arrangement -- Fastly (FSLY -3.35%)

Fastly provides an edge cloud platform for software developers that's secure, scalable, cost-effective, and blazingly fast. Its technology has quickly become a favorite for many of the most innovative internet companies in the world, including Alphabet, Microsoft, Shopify, and Slack

The company currently claims well under 1% of an addressable market that stands at more than $35 billion and continues to expand. But Fastly's sales are increasing at a compound annual growth rate of 45%. Fastly's growth will be driven in large part by the growth of its existing customers. It also plans to continue launching new products and moving further into international markets. The tech stock should be a huge winner over the next 10 years as it captures more of the fast-growing edge platform market.

2. Guardant Health: Harnessing the power of DNA

Genetic research is transforming how cancer is treated. It's also transforming how cancer is diagnosed. Liquid biopsies are tests that detect cancer by finding DNA fragments of tumors in the blood. These tests hold the potential to save lives by enabling early diagnosis of cancer. Guardant Health (GH -5.19%) stands out as a clear leader in the liquid biopsy market.

Guardant Health sells two liquid biopsy products that are already tremendously successful. Guardant360 was the first comprehensive liquid biopsy to win Food and Drug Administration approval. Used for the genomic profiling of all types of solid tumors, it helps match patients with the most appropriate cancer therapy. GuardantOMNI helps drugmakers screen patients for clinical trials evaluating experimental cancer drugs.

The COVID-19 pandemic has caused Guardant Health's growth to taper off a bit, but the company's long-term prospects remain bright. The estimated potential U.S. market for Guardant360 is around $6 billion. There's a much larger addressable market of over $45 billion for Guardant Health's LUNAR liquid biopsies, which are being evaluated in clinical studies for use in early cancer detection and cancer recurrence monitoring. 

3. Novavax: A coronavirus vaccine dark horse

The U.S. government's Operation Warp Speed (OWS) initiative has primarily funded the COVID-19 vaccine programs of large drugmakers. But one small biotech that could be a dark horse in the race to develop a coronavirus vaccine landed $1.6 billion in funding from OWS. That biotech is Novavax (NVAX -4.82%).

Novavax recently began a phase 2 study of its COVID-19 vaccine candidate, NVX-CoV2373. Some analysts referred to the investigational vaccine as potentially best-in-class after the company reported results from phase 1 testing. Novavax hopes to report interim results from its late-stage study of NVX-CoV2373 in the fourth quarter of 2020.

If NVX-CoV2373 wins regulatory approvals, it could be a key player in an estimated $20 billion global market for coronavirus vaccines. The company also plans to seek FDA approval for another promising candidate, flu vaccine NanoFlu, which could generate peak annual sales of up to $1.7 billion if approved. These are massive opportunities for a biotech with a market cap of around $7 billion.