Name this science fiction story, Part MMX

I remember reading this story in the 70s. It took place In The Future[sup]TM[/sup].

The earth had become so overpopulated that everyone was assigned some small portion, maybe a few square feet each.
That’s all I got.

Maybe you mean Billennium by J. G. Ballard, but your description is too vague for me to be sure.

Did this story have the protagonist discovering a room that had been boarded up and forgotten?

Did Captain Kirk find himself alone on the Enterprise with some foxy blond chick?

No?

Then I got nuthin’, too.

Does the protagonist live in a cubicle on a staircase until he finds a new apartment? That’s also from “Billenium”.

I’ll try to track down a copy of Billennium and see if that’s it.