What's more, after picking up the renovating bug, Tristan is currently working on another project. “I recently bought an 18th-century house in Kevelaer and I’m in the process of restoring it," he says. "I plan to open it as an Airbnb, because the process of owning and operating a holiday home is really fun. I love it!”

Tristan is also hoping to purchase and renovate another bunker on the complex – although, at the moment, few are for sale within his budget. “I would love to create a hobbit hole, inspired by The Lord of the Rings." We don't know about you, but we can't wait to see what Tristan does next!

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'How I made my dream home from a Cold War bunker'