NEW YORK (CNNMoney) -- Edward Peden and Dianna Ricke-Peden built their dream home in an unusual location -- an old underground missile bunker in rural Kansas.
Nearly 20 years later, they have turned that first step into a thriving real estate business.
Their bunker business, 20th Century Castles, helps sell decommissioned missile sites. They have closed more than 50 sales across the country.
Buyers, the couple says, like these hardened structures, which were designed to withstand a nuclear blast.
The so-called doomsday prepper movement helps drive interest.
One challenge: They typically seek all-cash deals because it's hard to get a mortgage to buy a bunker.
Check out some other bunker homes:
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