Hi,
The best Virtual solution nowadays is:
Hardware needs:
MB + CPU both support Intel-VT or AMD-V technology
Example:
MOTHERBOARD : SUPERMICRO X7DBE-X ~700$ per unit
CPU: 2x INTEL XEON X5355 BX80563X5355A ~1000$ per unit
RAM: 4x KVR667D2D8F5K2/2G ~200$ per unit
total 3500$
Software...