Substance 3D Painter is an application dedicated to texturing 3D models, so you shouldn't have issue creating the texture.
From the reference sent, I'd say the material of the coach is Denim, therefore I advise you to simply start with a Denim material. Something like this should do the job.
You can tweak the color, roughness, etc. but you'll need to add several layers (dirt, dust, etc.) to get a convincing result.
Best regards,
Cyril Dellenbach (Micro) | QA Support Artist | Adobe