Instead of painting, affix fabric to interior doors to change the look.
Purchase 100 percent cotton fabric wider and taller than the door to be covered. Clean the door. Wash, dry and iron to pre-shrink the fabric. Saturate the fabric in liquid starch and affix to the door like wallpaper. Use hands to smooth out air bubbles and wrinkles. Extra starch may be added for tough-to-stick areas. Trim to fit edge-to-edge.