I know it's a rude question, but it's been on my mind… I'm wondering roughly what I should be expecting to outlay when I finish my set-up? So I'm assuming it includes things like domain names, hosting for backups, email providers, VPN, etc. What's a good budget to set?
It really depends on what you're doing. In my case the soft costs like domains are pretty negligible compared to how much I seem to spend on more hard disks every six months. You might tell yourself, "96 TB of raw storage will last forever," but it turns out forever is about a year.
That's a slight exaggeration. I think it was about 2 years to get close to filling that up. Keep in mind that a chunk of that is unusable due to drive parity.
If I remember correctly ZFS keeps the whole array running whenever one is active (which is basically always). If I remember, I'll check my UPS when I get home to see the actual power draw. The storage itself is probably cheaper to run than the main server in the rack - a gen8 HP 360p, which is a bit on the old side and I'd guess not terribly efficient being a 1U piece with many small high-powered fans running constantly.
Electricity here isn't too expensive though, being public hydro power.