Essentially none. I was born in 1948; got my layout in 1955. We were "solid working class" or "middle class" (whatever that meant; meaningless now), as were many others in the neighborhood, so trains could have been bought, but trains were not a "thing" with most people I knew. I had a nice permanent Lionel 027 layout with 2 spurs and a passing siding (only 1 loco, though....). I never put a train around a tree.
But - one guy up the street did have a bit of interest; he had a Kusan "2-rail tinplate" Alco set, then later a Marx 666 set from Sears. Ran it on my Lionel layout a few times. I liked it. But, his interest waned and never came back.
A couple of other guys had AF sets, both PA sets of some sort. One was blue and silver. Neither guy had much interest in trains.
Another guy across the street was literally using his "old" Lionel 2035 as a doorstop (ever picked up one of those?). We were around 13; 1961 or so. I asked if he wanted it, and he said no. So, after we asked his mother, it was mine, and it went into a drawer for years. I actually fixed it up (not to be confused with "restored") when I was in my 40's, complete with a NOS tender from Madison Hardware, still in New York.
That was it. There must have been more, as you saw trains and layouts in stores, especially at Xmas, of course. We had at least one Lionel (AF too?) Service Station (an appliance dealer). But so far as my life was concerned, I was pretty much alone with my hobby. Trains were not broadly a big interest among the kids/adolescents I knew.
