A quick and simple method to get rid of the plastic new freight car look is to spray a light coat of Dullcoat.  This will take away the 'toy' train look of your layout.  If you don't have any Testor's Dullcoat you can use any Matte Finish spray to get the same results.  Just a simple spray to each side and let dry.  This can be done to any plastic kits also.

The sawmill has a permanent place in our hobby as an industry built in the sticks. The location of these structures usually is located far from civilization [ ... ]

I've finally added as much plaster cloth as I expect I'll need, and have moved on to priming the base before painting it.  Priming made it look unfamiliar, [ ... ]