A mattress on a pile of straw with a ratty old CASted blanket on it, warped wood flooring, a bare lightbulb hanging from the ceiling, peeling paint, drafty broken windows, maybe a bathtub. Sims don't care and they don't really deserve any better anyway. >:)
(Not sure, but it's possible I may need to take a break from this game pretty soon...)
Okay, probably not on topic but seriously have you ever tried to simulate poverty conditions on purpose? Most content is just so nice looking even if we don't take the time color coordinate, it can be quite challenging to make things look uncomfortable on purpose even when using CC specifically designed for it. :)