Here you can find Base Examples for Art

Artworks roughly on a 100-400 pixel canvas. 

Artworks with no shading.

These artworks are mostly appraised by a mod to get a true value. 30+ is a base.

These artworks are mostly appraised by a mod to get a true value. 60+ is a base.

  https://sketchfab.com/3d-models/faux-model-assignment-2-8e84121b44784009bdec530625f9fde0