Some types of clothing are better displayed with faces painted in high fashion colors, ethnic skin tones or other "real" detail. Lingerie retailers want mannequins with large breasts and protruding nipples, to fill the clothing better and to add "sex appeal." Painted nails, expensive wigs and pierced ears are other details that may add to a manikins' realism. Probably the most overlooked, but certainly one of the most important, features of a realistic mannequin is its pose. So often, especially in older mannequins, the pose is simply unbelievable. Relaxed standing or sitting poses tend to be most convincing.
It is not uncommon for mannequin refurbishing to cost more than some new mannequins, but the makeup and skin tones should reflect the money spent in both realism and quality. Remember to spend freely on mannequins and other display tools, as they will pay for themselves with increased sales, and cheap manikins are often exactly that - cheap. For realistic mannequins to really pull it off, they must be quality.