I purchased two 3D printed ruins from QP3D Wargames. One of these was the Ruined Waller Residence. They are 3D printed models. I bought the 15mm versions to use with Flames of War, but you can buy bigger versions for other gaming systems.
The first stage was to prime the model with a white undercoat.
Here is the ruin with a Flames of War 15mm Tiger for size comparison.
I think I will be using contrast paints on these models as a starting point.