Less than a month ago I bought my guinea pig, Beary, a brother and named him Oreo. I had them separated for almost two weeks but they would squeal at each other from their perspective cages, so they are now living in one.
Their habitat consists of those cubes you put together with the circle-thingies. I originally had a 3 X 2 habitat, each cube is about 14″. Well that wasn’t big enough. Now the cage is 4 X 2 and has two levels! We built a ramp and this way they both have their own areas if they want to. Right now they just follow each other from one place to the next. I do think they love their new mansion home.
Now I use bits and pieces of the cubes to make little apartments.