Noise in the render

Hello, I have a problem that on some parts of my model there is a lot of noise. It is not the first time this happened to me. Can you help me to get rid of it?

Overlapping faces.
Remove any duplicate objects
Remove any double vertices by selecting all vertices and W / remove doubles.
The recalculate face normals by selecting all faces and Ctrl+N

Thank you! You cannot imagine how much you helped me :slight_smile: