Hah, that might be slightly above what I'm ready to pay for a at-home server yes :) But given the right specifications and software integration, I'd probably be ready to pony up up to somewhere around 10K for a complete solution if it could replace all my existing hardware, even if it was more expensive than other options with worse tradeoffs.
You have 3-phase service to your house? Lucky. I wish I could get 3-phase here but I think it would require trenching like half a mile to the main road. I get by with a phase converter on my lathe but it's significantly less efficient.