If you want something more turn-key, go for a Synology box. Go for something with at least 2 drives like a DS220j for less than $200 or the slightly better DS223 for about $250. Just pop whatever drives you want in there, I’d suggest server-grade, NAS drives or SSD for better reliability. Setting this up to work with Time Machine is very easy and there are tons of walkthroughs online for setting that up.

For a more DIY approach, you can build a TrueNAS box (formerly FreeNAS). Tons of tutorials you can follow online that will tell you everything you need to go this route.

One thing to note, a NAS will only be available on your home network without additional configuration. TailScale is my recommendation if this is something you want to do.

If you aren’t already, you may want to use a solid state external drive or be sure that your router it allows the hard drive the sleep. I killed 3 external drives by doing this before I realized what the issue was.