If he runs the standard firmware he will only do 2kw, if he runs on low speed below 1.5kw.
Of course, he could try running them at over 3kwh and reach 75TH/s but even without that he would have to go out and in of that apartment only during the night as his neighbors might end his mining adventure prematurely. 

Probably he has at max 50 or 60 A, I don't see apartments there getting more, but still, even two of those things screeching all night long in the next room would drive me insane.