The price on these things have really come down.  I just bought a used one for $200 and an APW3++ for $200 off Amazon.  This will be my first foray into bitcoin mining and from the research I did there really isn't any cheaper way to get 4TH/s than an Antminer V9.

My electricity rate up here in Canada is 0.04 kWh so I should definitely be seeing profit.