One of the (many!) great benefits of HA is how easy it is to move your configuration from one host device to another. In most cases it’s as simple as backup on the old system, and install then restore on the new system.
Given this, you can safely start with any of your existing options (used PC, NAS) to start your exploration. Then if you want to upgrade/change approach to a different platform after a few days, weeks, or months, you can easily do so. Personally, I progressed from a RasPi4, to an old laptop, to a dedicated BeeLink mini PC running ProxMox.
One of the major considerations (depending on where you’re located) is the idle power consumption of your device, ‘just an old PC’ can quickly become expensive (30-75 watts idle is not uncommon for an ex-desktop/ gaming rig, 4-10 watts is possible for well-selected x86_64 hardware). haos itself doesn’t need all that much performance (>=32 GB disk, >=4 GB RAM), but if you have esphome builder, voice recognition, video surveillance et all, you might quickly need (a lot) more.
Starting your experiments in a VM on your NAS would be a sensible choice (if you can spare 32 GB disk and at least 2 GB RAM), to give you a feel which direction you might be taking. Using old PCs is only sensible if their idle power consumption is ‘reasonable’ compared to your electricity costs, because you will want to keep haos running 24/7 for a few weeks, if you want to test the waters.
There are plenty of pretty decent x86_64 devices on the markets, be it used or new (n100/ n97/ n150, etc.), idle power consumption can be really good - and prices tend to be reasonable.
Just becareful, their are lots of beginners who get lost in the weeds building a self-installed HAOS and things don’t work. It may be great for those with lots of computer, programming, hardware experience but sours the inexperience beginners.
The Yellow has been discontinued, however, ameriDroid did secure the last available units and we have stock for both Power Supply and PoE options at this time.
That entirely depends on what you consider building your own…
My train of thought was:
used market:
one of the semi-recent popular thin-client like devices (futro, wyse, igel, hp, …), at least Atom j4xxx or ryzen embedded - depending on your requirements you might need to upgrade the SSD or (less likely) RAM, shouldn’t be hurdle; ~5 watts idle is very reasonable, performance quite good (although there are certainly things that would prefer more)
one of the 1 litre ‘tiny’ PCs of the big four (Dell, Fujitsu, HP, Lenovo, …), things that don’t make the bar for windows 11 tend to have good prices - roughly i5-6500t/ i5-7500t class, usually with 128-256 GB SSD and 8 GB RAM; idle power consumption probably in the ~10 watts range, still very decent performance, just works - nothing to do.
new:
tiny PCs with alderlake-n n100/ n97/ n150 ordered from abroad; similar performance to skylake above, a tad more risk for buying, 5-6 watts is very reasonable
NUC-like mini-PCs, more expensive, probably also in the ~10 watt idle range, more performance
modern 1 litre tiny PCs from the big four, more expensive, very fast, also roundabout ~10 watts idle.
Installing haos, ~5 minutes, setting up the basics ~half an hour. Connecting up a USB- or networked zigbee coordinator, ~5 minutes if you roughly know the process (~have read up on it beforehand) - if you don’t, there are some pitfalls that can leave you scratching your head - but it’s still straight forward.
Yes, you can certainly build yourself as well (mITX, µATX, …), but guesstimating the idle resulting power consumption will be harder - unless you have special requirements (like dedicated graphics cards for LLM stuff or huge disk space (video)), it’s probably not sensible for this use case (because there are pretty decent options in the <=1L tiny PC range); and even if you do, there are pretty interesting SFF PCs from the big four on the used markets offering ‘some’ (limited) extensibility).
The problem is not so much finding or building something, but correctly determining your medium term performance/ disk/ RAM requirements - enough (with healthy headroom) to make do, at low idle power consumption - and then identifying the best bargains on the market. If electricity prices or hardware costs are not a factor, this gets easy - but usually they are (and it’s best to get a grasp on your rough expectations first, with the understanding that you might add unforeseen additional requirements (for me, that was esphome builder and dabbling into voice detection, which invalidated my first -cheap-cheap- hardware, without those new requirements, my AMD GX-212JC with 16 GB M.2-SATA and 4 GB DDR3-SODIMM would have remained comfortable) soon).
Thanks for the detailed reply. I’m starting on a Microsoft Surface Pro with a dock, and will go from there. I have a few older PCs available which are not used, and don’t mind dedicating one of them singularly for HA.