Symbolism, Imagery, Allegory
This is a biggie, symbol-wise, Shmoopers—you know something funky is going on when a guy puts all of his furniture out on the lawn and arranges it exactly as it was in the house. Like, if you need to sell it, why set it up exactly like it was when you were using/living with it?
There are a lot of different possible answers and interpretations, but one possibility is that our protagonist's love life has clearly taken a bad turn—and his empty house symbolizes his empty heart.
Beyond that, though, there's also something pretty powerful about putting all the stuff you shared with someone out there on the lawn for the world to see. We get several references to the fact that the neighbors are watching the older man and the young couple, which kind of suggests that they're a bit nosy. So maybe the older man putting all his furniture out there is his way of just confronting all the gossip and whisperings that go on when something dramatic happens—you know, like a divorce or death (we assume the guy has been through at least one of those).
In any case, this guy has re-created a mirror image of his home life that's exposed to the elements and scrutiny of others, which gives us the sense that he, too, is feeling exposed and perhaps less secure.