U.S. property owners with just one rental house can now get cash from Wall Street to buy more.

Cerberus Capital Management LP, which initially targeted landlords with multimillion-dollar loans, is financing low-volume deals for small investors through its FirstKey Lending, with looser terms than government-backed mortgages from Fannie Mae and Freddie Mac, said Randy Reiff, the business’s chief executive officer. Blackstone Group LP’s rental lending arm, B2R Finance LP, is making a similar push to mom-and-pop landlords.