Check out a nice Cracked Paint material by Matthew Taylor which is now available on Gumroad.
MT_Cracked_Paint.zip containing:
Cracked_Paint.sbs (with comments), Cracked_Paint.sbsar, 5 pre-exported 4k png textures (AO, baseColor, height, normal, roughness), and 6 custom utility nodes used in the creation of the material (Bidirectional_Bevel, Difference_Grayscale, Highpass_HQ, Is_Higher, Protrude_From_Height, Smudge).
100% procedurally generated material made in Substance Designer. The material is dynamic and simulates the cracking and peeling of a painted wall. The controls are simplified down to a ‘decay’ slider and some settings for changing the paint colour, roughness and normal intensity/format. More details and examples can be found here.
You can learn more here.