When choosing your paint colors, remember every space is unique. Everything from light quality to your floor coloring will have an impact. Keep in mind chip samples may not be accurate. Paint will always appear much lighter and intense on your walls. So to arrive at your desired color try choosing your sample twice as subdued and twice as dark as you envision.
All paints are translucent so it will take more than one coat for proper coverage. White primer will give your best performance under all colors. Any other colors added to your primers may lessen your coat applications, but not result in its truest and cleanest final color.