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!

Liked this? Click the Like button above. And click the Follow button above for more great stories from loveMONEY

How one man turned a dilapidated Cold War bunker into an amazing home