Want to start investing in real estate? You might already have a big piece of what you need to build a rental portfolio.

• Homeowners can start real estate investing by leveraging their primary residence.

• One strategy, known as house hacking, involves renting part of your home to offset mortgage costs.

• Converting a primary home into a rental can also expand your real estate investment portfolio.

If you’re among the 65% of Americans who own a home, that could be enough to kick-start a real estate investing career.

“Your primary home is often a really great starting point for building a rental portfolio,” CPA and part-time property investor Amanda Han told Business Insider.

She and her husband, Matthew MacFarland, started their accounting careers in the real estate group at a Big Four firm. In 2008, they launched their own firm, Keystone CPA, specializing in tax strategy for real estate investors.

Having spent their entire careers working alongside property investors, the CPA couple has concluded that people tend to overlook the potential of their own homes.

The California-based couple, who own rental properties and are invested in multiple real estate syndicates, describe two main ways to leverage your primary residence.

“I would encourage people not to be afraid of house hacking,” said MacFarland, referring to the strategy in which you rent a portion of your primary residence to offset or eliminate your mortgage payment.

“We’ve seen a lot of clients be very successful in getting their first deals under their belt that way, where their tenants are paying for half of their mortgage, if not more.”

It’s cost-effective for two main reasons: One, owner-occupied financing tends to come with more favorable terms compared to financing for investment properties. That means, you may be able to lock in a lower down payment and interest rate than if you bought a true investment property that you didn’t plan on living in. You may even qualify for an FHA loan, which is a government-backed mortgage that allows people to buy a home with down payments as low as 3.5%.

Two, the rental income from your tenants can lower your housing payment, or even completely eliminate it.

This strategy isn’t for everyone — you’re sacrificing privacy, especially if you plan to rent a spare room in a single-family home — but if you’re looking to build equity quicker while lowering your overall risk, the benefits could be worth it.

Early in Han and MacFarland’s investing careers, they moved homes. Rather than listing their original primary residence for sale, they kept it and converted it into a long-term rental.