Duplex Safety

[Abou C.]

If one owns a 4 unit two bed room duplex with a finish basement once green lighted to do so.  Should the whole building be hard wired for fire safety or would a better operated do?.

 I asked because I spoke to a investor way back when who owned many units, and one day there was a fire and a talents son amsted died due to their behavior. But since the owner had the fire department tour and recommend safety guide and etc. This investor saved him self from going to jail since he did he's job correctly.  Also with 4 units mistakes can happen,  so is hard wired and sprinkles necessary for a duplex of four unit?