I'm not an expert on handpainting, ok :( You may build the model itself in Maya. Or other modeling tools. UVwrap this. Then get to Photoshop, or 3D Coat, would be easier to paint the model. If you look over the process; there doesn't seem to be any normal map involved.
I think that's handpainted. Usually, no normal map. Mostly just AO and colors. https://www.artstation.com/artist/ybourykina Look her up. More breakdowns here. http://zbrushtuts.com/2016/07/28/top-10-3d-art-and-breakdowns-by-yekaterina-bourykina/