X Kw in any room is possible with proper wiring, upgrading your breakers at the panel won't let you run 8kw from those miners all on one line however. lets work it backwards from your existing setup
you have 8kw worth of mining equipment, you need ~67AMPS available to you, without having one of these to check it's inrush current i'm going to say you actually need 80 insted. if your house is wired with 12gauge wire(as opposed to 14, how cheap was your electrician) you could use 4 20 amp breakers. Assuming your electrican used 15 amp outlets you'll need to replace them as well, then it's just 3/line(so 2 lines per outlet)
or as mentioned instead of rewiring a room and running 80/200 amps residential get them hosted
Not if you run at 240, see my post above.