Next you are talking about 3 racks of space (you can fit 42U in a rack), plus extra power, figure $3000 per month in a less-expensive colocation space.
Gigabit switches, cabling, etc. figure another 5K or more, depending on the quality and features you want.
Bandwidth will be metered by your colocation provider, prices can vary, usually you will be given 5-10Mbps as part of the rack.
So figure $210K plus $3K per month or so.
Not sure exactly how much power, but 2x 30A power feeds will give 48A usable power, which is just about 1.5 amps per system. Whether that is enough for 8 cores (2x quad core), I don't know; will depend on amount of memory and disks.