Before we moved to NYC, we had a little rental house with a room we devoted just to the cats.
Before that I lived in an apartment that had two bathrooms and that second bathroom was dedicated to the litter boxes.
Now that we live in the city, we don't have a ton of space to work with in our apartment, though we do have more than some people have.
Since we don't want the litter boxes to be a central focus in our place, we use a three panel screen that I'm sure came from Target. It's very basic but has held up very well over several years (when I first got it, I managed to put a head sized shape in the slats, and didn't think to gently push it straight again- thanks to my BFF who came to visit me, the slats are flat now).
We keep a vacuum right next to the boxes, and when we clean the litter (and by that I mean E, since pregnant women aren't supposed to clean litter), we also vacuum (by that we I do mean we, though mostly it's E because he's there anyhow to clean the litter).
The screen also limits the cat's entry and exit so that the litter is not tracked through the apartment.
That little wooden storage stand keeps the plastic baggies and all the cat treats in one place.
From the living area, the boxes are invisible. Unless of course someone drops a stink in the box. We have a motion sensitive air freshener plugged in to help with that.
Eventually we'll have a kid who is mobile, and we'll have to find another solution. But that's down the road. For now, this works pretty well.