The well-known property insurance company that serves the military (and sponsors A-N game) may still offer its small SA property policy at roughly $5-$8/month, with full replacement no deductible on class ring (if it's blinged out it may need a separate rider) and $50 deductible. It’s designed to cover computer gear, gaming gear, uniforms, expensive sports equipment, engagement rings (ditto rider). After graduation, the new ensign or 2LT closes out that policy and starts a new “regular” personal property policy, which covers their stuff whether it’s in their car, in a storage locker, parents’ basement, sponsor’s closet, at a buddy’s while deployed.
There are a handful of well-known companies who understand how to cover AD folks’ stuff while deployed, at school, TAD/TDY, while separate from spouse who might have stuff and 1 car living at her parents’ in another state during deployment or school or no-dependents tour or no-co-location dual military couple in two states.