Find the month a NAS stops costing more than a cloud subscription.
A four-bay NAS with spinning disks idles around 30 to 50 W.
The NAS pays for itself after 38 months
Over five years the box costs $2,226 against $2,880 for the subscription. Cost is only half of the decision. A NAS in your house is not an offsite backup: a fire, a flood or a theft takes the original and the copy together, and so does ransomware that reaches a mapped drive. The arrangement most people end up wanting is the box for fast local restores and a cheap cloud tier for the copy that lives somewhere else.
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