You can start hoarding data at any budget and in any living context.
The most basic, primitive, and easily usable/accessible hoard can start in the form of an external hard drive plugged directly into your PC. I have met people who store hundreds of terabytes of data across many external hard disks in this manner.
While this approach "works" for many people, more technically-savvy hoarders understand that keeping their hoards on external hard disks is a flawed approach that doesn't scale well, provides limited availability, and doesn't intrinsically account for backup/redundancy. Hence, you get to see the "crazy setups" with "back-ups upon back-ups" in this sub.
Fortunately, you don't need a "crazy setup" to start hoarding a modest amount of data. In your living context, you can start by investing in a simple NAS.
A NAS, or Network-Attached Storage device, is basically just a PC with a bunch of disks installed. There are off-the-shelf options that you could go with (Synology) however most people in this sub would recommend that you use software like TrueNAS, Unraid, etc. which you can install on a typical desktop PC with internal disks installed. What sets a NAS apart from simply using external drives is that a NAS provides an always-on location on your network where you data can live, and also sports features and functionality, redundancy layers, pooling, etc, all of which you cannot readily/easily accomplish with external drives alone.
In a shared living situation where you only have access to a single room, form factor and noise are probably going to be your key constraints. You will want to start by identifying how much space you have that can be allocated for a PC to use as a NAS. This PC could be as small as a raspberry pi with a few attached disks, to as large as a full ATX tower with 8+ 3.5" bays. You also don't need a particularly powerful PC to use as a NAS; anything from the past 10-15 years will work as a dumb NAS, however newer machines will benefit from lower power consumption and broader functionality beyond working as a simple storage device.
Now, moving onto "backups upon backups"... How much do you value your hoard? How devastated would you be if a brownout fried your NAS and toasted all of your hard disks? Put a dollar value on mitigating that sadness, and you now have your backup budget.
Backups can take many different shapes, forms and sizes. To provide you with the simplest example, let's say you've just finished migrating your hoard from an external hard drive onto a NAS... Maybe the external drive is now your primary backup. Maybe you can encrypt the external drive and keep it in a locker at work or somewhere off-site so that your hoard is protected in-case your house burns down. Maybe you can purchase a cheap cloud subscription where you can encrypt and upload some of the most important data from your hoard. Maybe you "sync" your NAS with these backup locations on a routine basis so that your backups are fresh.
Generally speaking, the more important your data is, the more disparate backups you should have. On the flipside, if you're hoarding something silly like Linux ISOs, maybe you don't need any backups at all!
Also, and this can never be repeated enough, if you use any RAID/zPool redundancy in your NAS, this is NOT a backup.
Happy hoarding!
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