Courtesy of Zack Nelson
- YouTuber Zack Nelson built a bunker in his backyard for under $100,000.
- He's documented the nearly-three-month process in a series of videos.
- Nelson said he's not a prepper, and has mainly taken on the project to boost his YouTube channel.
YouTuber Zack Nelson built an underground bunker in his backyard for under $100,000 in under three months.