Just as a quick follow-up, I pulled the trigger on a Trezor Model T as my hardware wallet, which will serve as a failover in the event that other wallet devices like computers, mobile phones, etc. get lost, or stolen, or malfunction, etc.
One of the reviewers on Amazon thinks you can build this device with a Raspberry Pi
https://www.amazon.com/gp/customer-...ef=cm_cr_dp_d_rvw_ttl?ie=UTF8&ASIN=B07B8Q2G3K
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