My personal strategy was to buy reman’d HGST drives off Amazon and take the acronym “RAID” literally.
I think it was ~$30 for a 4tb drive (there are other sizes, i just picked one that worked for me) and I filled my nas with them and dedicated two drives to redundancy. I set them all to raid 5 and then put an extra drive in the last bay and configured it to be a “hot swap” - essentially raid 5 means one drive can die on me and the data is recoverable. Then the nas will automatically pull the hot swap online and begin the recovery process immediately if one does die cuz if two go there can be data loss. Your could even raid 1 the drives and then if one dies the other is fine.
I got lucky and haven’t had any fail yet but if you’re willing to put up with and plan for a possible drive failure you can get some seriously low $/TB.
Depends on what’s worth it to you, but i like my redundant array of inexpensive drives.
Home Assistant on a pi with a zigbee / zwave stick imho, no 802.11 devices.
Zigbee is an RF standard and I don’t think there’s licensing so the devices tend to be cheaper but more wild west-y, while zwave is a controlled standard and has the cost overhead associated with that. Both standards support nodes being repeaters on the network so a chain of devices can pass instructions to devices not necessarily in range of the base. Also because they’re established standards, zigbee/zwave devices will still be useful after the company that makes them goes under, unlike fly by night wifi crap.
If you insist on having it wifi based, look into ESP custom firmware flash-able devices - there are open source firmwares that you can know won’t be trying to make any shady calls home.
My solution to “iot devices be shady” is to run my own network connected base and then everything else is a dumb device that takes commands.
Oh and if you do go ha on a pi, buy a usb hdd adapter and boot from that - I’ve found sd cards to be unreliable.