Cold storage advice

self.Bitcoin1m ago
I have multiple Bitcoin on a cold storage device. I'm joining the military. Could I get recommendations on where to store the cold storage device? I don't think I can take it to boot camp. I also don't like the idea of leaving it with family. They're not very responsible, sounds stressful. I know leaving multiple Bitcoin on an exchange is a bad idea, but it sounds like the easiest option. Maybe the Coinbase vault?