MTH coaches come with the interior piece the same color as the outside. One would think it would be easy to mold them a different color. So I’ve been painting mine and adding figures. Some of the coaches had some wild color schemes. Figures are those ebay ones from China. ALL had black hair, so some re-paint was done on that and the skin tones changed. For standing figures, I shortened the legs some. 
This gray one I did first.
Observation cars usually had different color seats. I also painted the table tops and the bar. Mirror behind the bar also. 2 cars to go!
Here’s a shot of the cars outside, at eye level. I think it adds realism.
