This is how i started, and while it has it's limitations and possible issues, it's a perfectly valid self.hosted approach.

The basic idea is to stay cheap, save on hardware using something you already have available and adapting to it's limitations. My choice has been an older, but powerfull, laptop which has quite a few advantages:

• Doesn't need an UPS, it has an integrated battery.
• It's fairly low-power, which is good for something on 24/7
• It doesn't need an additional monitor+keyboard for console acces
• It uses little space (specially compared to a PC with monitor&keyboard)
• Can fit vertically behind furniture, if you don't have a place for your self-hosted rig
• Come with WiFi out of the box

But it also have some drawbacks:

• Limited storage space (usually one SDD or maybe one NVME and one SSD)
• Limited upgradeability CPU/RAM wise
• Louder fans under heavy load
• Usually one (or even none) internal network interface card
• An always plugged in battery will swallow over time and can be a fire hazard

Most of the drawbacks can be overcome with modern USB devices. Today's USB-C bandwith, but even older USB 3.0 bandwitch, is more than enough to cater for your home needs. In fact, if you use WiFi, even the cheapest USB drive enclosure will be faster than that. If you have wired ethernet at home, 1Gbps will still be faster than your mechanical drives, and USB will not be a bottleneck. If you have all SSD's over USB and a perfectly wired 10Gbps ethernet cables and plugs, well, why cheap out on an older laptop then?

As a final word, this simpler approach works very well and might be all you need. The limitations come from the single point of failure that having only one piece of hardware implies: when it goes down, for hardware failure, software bugs or just maintenance, all of your home network will be offline. Your kids will be pestering you that their online-gaming is broken, their social media doesn't work, and your wife will be pissed off that the streamed movie doesn't work.

Let's focus. You need RAID storage, which means at very least two hard-drives (or SSDs) in RAID1. Better would be many devices on RAID6 or such, but letìs stick with two RAID1 mirrors for the simple approach.

Assuming your laptop cannot host two drives internally, you need to buy an external device. Laptops nowadays only come with various USB connectors, so i will not talk about E-SATA or other connection types, but only USB. Those are also the less expensive, so it's a win-win for the simple approach.

A few key concepts to follow:

• Prefer USB-C over USB-3
• Don't go anything less than USB-3 (USB-2 and USB-1 are just too slow)
• Get a multi-disk enclosure (2 disks, or even better 4 disks)
• Get an externally powered enclosue, always
• Get a JBOD (Just a Bunch Of Disks), not a RAID enclosure
• Get a small UPS to keep those disks spinning on power loss
• Do not be cheap on this: get a reliable brand and model.

As i said above, USB-3 and USB-C are more than capable to sustain disk troughputs and network loads, so USB will not be your bottleneck. but USB is quite unreliable, bot the protocol or bus itself, but the USB devices are usually low-quality. To ensure you have no issues over time, buy only reputable brands enclosures, do not save money on this item, and avoid RAID enclosures because i will be showing you how to leverage Linux built-in software raid, and JBOD enclosures have a better quality/price ratio.

Since laptops have limited USB ports, get only one big enclosure to fit all your drives, not many smaller ones. Prefer one which is externally powered, because they are more resillient, and buy a cheaper UPS power strip (anything in the lower end should fit) to keep the disks spinning then the occasional power outage will strike. In fact, having a laptpo which will survive a blackout while the disks don't, it's not a good nor safe idea. (remember: UPS batteries will need to be replaced every year or two, do it)

The second issue with using a laptop is that you will need at least two, better three, wired ethernet connections to use your server:

• One LAN interface, to talk to all your home devices
• One, or better two, WAN interfaces, to talk to your one, or better two, ISPs (Internet Service Providers)

I suggest to avoid using WiFi because or reliability and bandwidth, so you need three ethernet NICs. If you are lucky, your laptop should have one, the others needs to be added via USB network cards. This is where things get a bit comples because USB network cards are quite unreliable. Luckly Linux nowadays support most of existent USB network cards, but in my experience they tend to fail quite easily. Some suggestions:

• Buy a known brand, stick to 1Gbps cards
• Prefer USB-3 ro USB-C (seems more solid kernel drivers?)
• Avoid “multi-hubs-with-also-ethernet” and buy devices that does only one thing: networking
• Keep them cooled: heat will make them fail more than often

If you experience links going down, buy a different brand / model and hope for the best.

Your laptop will be your server and your router. Which means that all your services will run on it as well as all your routing tables, failover between ISPs and such.

Your server, or your laptop then, will need to be beefy enough to host any service you will need. In my experience, this is not a big issue. For low power laptops, a good video card might be useful for on-the-fly AV1 / x265 video decoding (if you want to host a media server like JellyFin).

Your laptop will be your server and your router. Which means that all your services will run on it as well as all your routing tables, failover between ISPs and such.

This means that if you mess up or need to reboot the laptop, your home will lose internet connection for a while. Also, if your laptop dies for any reason you will not only lose all your self-hosted services (until you restore a backup/replace hardware) but also everybody at home will be cut from internet.

Setting up routing with multi-ISPs (failsafe, or load sharing…) will be done manually with a few routing rules and settings (see Routing on the Home Server, Network Configuration for the Home Router and such pages).

While less glamour than using a fancy web GUI, it fits the same purpose and maybe it's also interesting to learn. This approach doesn't limit you to anything, actually might even be more fun than the advanced approach, but more error-prone e less resillient.