I have maybe half-dozen locos and maybe 30 cars, H0. All East-German, made in 1970s. Two big boxes, opened them only once since I moved to my last flat in 1989... Plus toy-trabants, buses, trees, stations, houses, etc.
H0 (16mm track) were not as popular as TT (12mm) here. My co-worker was illegally trading them ("speculation" was a crime in USSR) in late-80s, when we studied in school. An interesting 12mm engine could cost up to 400 rubles (average salary was 200 rubles a month).
Railway models were "toys for Fathers" here

Like "My daddy bought himself a new engine for my birthday"

In MSK there was an East-German store, called "Leipzig", and they had a huge model railway there, like 10x10 meters, with stations, towns, tunnels etc. We went there just to watch it working when I was a kid.