Amazon offers its Prime members the SentrySafe 500 0.2-Cubic Foot Fire-Safe Box
in Black for $20.84
with free shipping
. (Non-members can spend $25 or more to qualify for free shipping; otherwise, shipping costs $13.69.) That's the lowest total price we could find by $13. Sales tax is added where applicable. It's certified for 30 minutes of fire protection and features a key lock.