Buy the enclosure first and the drives second, and you’ll likely blow the budget — because a diskless box stores nothing until you fill it. Prices below come from US retailer and manufacturer listings checked in 2026, so treat them as a realistic range rather than a quote.
What Is A Realistic Budget For A Two-Drive Home NAS?
The enclosure is the cheap part. Drives are where the money goes, and doubling capacity is the single biggest cost lever you control. Here is what the current listings actually support.
Add the enclosure and the $350–$1,000 band makes sense: a modest box plus entry drives sits near the bottom, a nicer chassis plus 8TB drives lands mid-range, and anything Pro-grade climbs past it.
Enclosure And Drive Prices Worth Knowing
Those are expansion machines, not starter boxes, and they show how fast bay count pushes the total up.
On the drive side, Seagate’s IronWolf line is the common pick for home NAS builds.
Every one of those numbers moves with seller, capacity, condition, shipping, and date.
| Build Level | Typical Drive Cost | What It Fits |
|---|---|---|
| Entry two-bay | $390–$500 (two 4TB) | File storage, phone backups |
| Mainstream two-bay | $600–$710 (two 8TB) | Media libraries, multi-user homes |
| High-capacity two-bay | About $1,080 (two 16TB Pro) | Large archives, 4K media |
| Six-bay enclosure | $789 before any drives | Room to grow over years |
| Rackmount enclosure | $609 before any drives | Rack setups, small offices |
| Single 8TB IronWolf | $299.99–$349.99 | Adding capacity later |
| Single 4TB IronWolf Pro | $281.00 | Smaller mirrored pair |
Seagate states that IronWolf drives are compatible with many NAS systems, including Asustor, QNAP, and Synology, but always check the enclosure’s official drive-compatibility list before buying. If you want to compare sealed, budget-friendly boxes instead of building from parts, this roundup of affordable NAS units worth testing covers the models that keep the total down.
Why Usable Capacity Is Smaller Than The Label
A two-drive mirror gives you roughly one drive’s worth of space, not two. RAID 1 copies everything to both disks, and formatting, system reserves, and snapshots shave more off the top — so two 8TB drives yield about 8TB usable, not 16TB.
RAID is also not a backup. Deletion, malware, theft, fire, and filesystem failure destroy mirrored data just as fast as unmirrored data. Budget for an external drive or cloud copy, and a small UPS, or the first power flicker becomes the story.
Cheapening out on drives is the other trap. Use matched-capacity, NAS-rated 3.5-inch SATA drives the enclosure officially supports, and skip shucked, SMR, or refurbished units unless you accept the reduced warranty and unknown prior workload. Seagate’s IronWolf NAS drive specifications list the workloads these drives are rated for.
One more cost people forget: the operating system. Synology runs DiskStation Manager (DSM) and QNAP runs QTS, and each vendor’s features depend on model, firmware, and hardware. Check what your chosen box actually includes before assuming a feature is there.
How Should You Spend The Money?
Put the budget where it buys usable terabytes.
Buy matched drives in one order, budget for a backup drive and UPS alongside the NAS, and never expose the admin interface straight to the internet — use the vendor’s secure remote access, MFA, updates, and a unique password.
Common Questions
Do I Need To Buy Drives Separately?
Most NAS enclosures ship diskless, so drives are a separate purchase. Some bundles include drives, but check exactly which models and whether they are NAS-rated. A diskless enclosure cannot store data until you install drives, so the drive cost belongs in your budget from day one.
Is A Two-Bay NAS Enough For A Typical Home?
For most households, yes. Two bays support a mirrored setup for file storage, phone backups, and media, and one drive’s worth of usable capacity covers years of photos and documents. Move up in bays only if you expect large media libraries or want room to expand without rebuilding.
What Else Should I Budget Beyond The NAS And Drives?
Plan for an external or cloud backup, a UPS to ride out power dips, and possibly a small network switch or faster router. Those extras add cost but protect the data you just paid to store — skipping them turns a mirrored setup into a single point of failure.
Sources
- Seagate. “IronWolf NAS Hard Drives.” Source for IronWolf and IronWolf Pro drive pricing and NAS compatibility.
- QNAP. “TS-264 Series Desktop NAS.” Source for QNAP NAS enclosure pricing and bay configuration.