What an interesting paper you found! Home ownership stats in contemporary times are quite misleading because of debt. Most home owners now are still paying rent in the form of a mortgage to a bank. In the 50s most home owners genuinely owned their homes 'free and clear'. The exact rate was 56% in the 1951 per your paper (which was a local low), and now it's at 40% which is a local high. And the contemporary demographics are all messed up - it's largely driven by older to elderly individuals in non-urban low-income states.

As for number of occupants, the 50s had a sustainable fertility rate. That means, on average, every woman was having at least 2 kiddos. So a median 4 occupant house would be husband, wife, and 2 children living in a place with a master bedroom, kids room, a combined kitchen/dining room, and a living room. Bathrooms, oddly enough, did not count as rooms. So in modern parlance it'd mostly be a 2/2 for up to 14% of one person's median income, and 0% in most cases as most people 'really' owned their homes.

We definitely have lots more gizmos, but I feel like that's an exchange that relatively few people would make in hindsight.