Is this an "infrastructure" mining unit (network, cabling, power) or is it a "mining" unit (miners included). What sort of final costs are you looking at? I have someone looking at making an infrastructure unit, his costs were looking at 2.5 ish BTC at current prices. Currently have access to a location with very, very cheap power and as NotFuzzyWarm said - rapid deployment and easy scaleability without much physical legwork (running cables, running network, setting up routers) is a critical value-add for this kind of project.