Along with FHA, a little known financing instrument called a contract for deed have helped low-credit borrowers, according to Daren Blomquist with RealtyTrac.

More than 103,000 contracts-for-deed were recorded nationwide in the five years following the end of the Great Recession (2010 to 2014), a 10 percent increase compared to the previous five years (2005 to 2009).

Contract for deed structures have been popular in the Rust Belt.

Some of the counties with above-average increases included Trumbull County/Youngstown, Ohio (136 percent increase); Wayne County/Detroit, Michigan (63 percent increase); Genesee County/Flint, Michigan (53 percent increase); Marion County/Indianapolis, Indiana (46 percent increase); Dane County/Madison, Wisconsin (26 percent increase); and Hamilton County/Cincinnati, Ohio (24 percent increase).

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