i know railroads stuffs have lots of supplies that can be used for dioramas , i did a great provision of it to use in dioramas, terrain grains, various grass types and lots of people in N, HO and 1/144 scale (1/72 boxes are for planes)
some i used for sci-fi dioramas
these are in n scale (1/160), i prefere to buy unpainted that cost very low respect the painted versions and comes in large number and lots of poses (cheaper way always!). And are all in hard plastic!!! not as common 1/72 soldiers in soft plastic.
For tracks basically i use same steps, but i wash and paint with enamels .
This is my last tank in the stash but actually is non on workbench. (even here i scratched something )
Waiying for final pictures