I bought a bag to use in my Railking passenger cars. I don't mind sitting and painting (I listen to sports talk and that helps me). I knew what I was getting into so it didn't bother me in the least.
I did exactly what MWB stated. I started with just one color and painted as many figures as I chose to using that one color. Let things dry, then used a 2nd color and did the same - painted all the figures that I wanted to have that color. Etc until done.
BTW: they are undersized like Arttista ones are, which didn't bother me since used in a passenger car - I had to cut the legs off the sitting figures to use them in the passenger car seats but the fact that they were a bit undersized turned out to be a benefit as their height was a nice size matched to the cars' windows.
- walt