I'd been thinking and I'd reach to the conclusion that a computer, with a Intel Core i5 (5th Gen onwards), 12Gb+ RAM and a SSD of 500GB would to the job, for everything I've been reading these last couple of days. I could even change the i5 for an old Xeon (seeing the benchmarks), which would be cheaper.

But from that last post of yours, I gather that there's no real point on setting up a server atm, unless I already have all the parts, because the network has enough servers and I'd be loosing time and money in electricity... Not what I was expecting, but if things are that way atm, not much I can do i guess