> 20000 / 8 customers / 40 USD/mo = 62 months just to recoup CPU and RAM let alone other components.

the most important question is the power, such a setup will blow through easily 500W of power. Granted, a datacenter may not pay 33 ct/kWh but even then, 1/3rd of the monthly income will just go towards naked electricity, not including cooling.

Electricity costs are ridiculous.