Thanks for all of the great advice.
And thanks Robert for those great pictures.
I think that if I let my small grandchildren run the colorful little Tinplate cars for the first few years, they will relate to the hobby much more quickly than having them run the flat painted, realistic cars.
And, I know that this is heresy, but I will probably have a small conventional locomotive pull the cars, instead of trying to get a Tinplate locomotive. I'm trying to stay cheap and simple to start. A small diesel Plymouth would look great. (May have to rig something to get it coupled to the first car, but that should be easy.)
Thx,
Mannyrock