If your clients are having a hard time deciding what color to paint a room, you can suggest painting the room multiple colors. Using multiple colors has benefits such as differentiating zones or simply making it look beautiful.
Andrea Von, HOUZZ, suggests painting a room multiple colors to give it an ombre effect:
"One of the most beautiful things about paint is that you can mix it to the exact shade you desire. This also means you can create a graduated, ombre effect on your walls for something truly special. This darker ceiling creates a cozy effect, but you could reverse the colors and go light at the top for an airier feel. If this paint effect seems too tricky, you can always cheat with ombre wallpaper."
Head over to HOUZZ to see the other reasons that you should paint your walls more than one color. Also check out these images below: