With traditional mortgages for lower-priced homes hard to get, some home buyers are turning to riskier alternatives, like seller-financed loans known as “land contracts” that don’t involve a bank.

About 1.4 million Americans have active land contracts, a type of financing in which buyers don’t get full legal ownership of a home until they make their final payment, according to a new report from the Pew Charitable Trusts. Pew has estimated that 8 million people have used the contracts to pursue homeownership.

Some buyers prefer land contracts because they can be arranged quickly and often have lower upfront costs than mortgages. They also offer an alternative to buyers who can’t qualify for a traditional home loan because of poor credit.

But the arrangements lack consumer protections available with traditional home loans and can leave buyers worse off financially, Pew found. The report was based on a survey of buyers as well as interviews with dozens of public-interest lawyers in 26 states who have represented buyers.

With land contracts, the home buyer agrees to pay a certain amount of money at a given interest rate over time. Data on interest rates for land contracts are hard to come by, Tara Roche, project director of Pew’s housing policy initiative, said, but what information is available shows “somewhat higher” interest rates than for mortgages.

The terms vary and can be as short as five or 10 years or as long as 30 years. Most are used to buy properties valued at less than $150,000, where traditional mortgages are hard to get, largely because small home loans are less profitable, Ms. Roche said. (Researchers have found that the arrangements are concentrated in lower-income neighborhoods with scant levels of mortgage lending.)