What's in there? Getting yourself a jumping off point palette makes it oodles easier to nail down a paint color. Like a rug, chair, picture, even just a pillow can give you clues about what direction to go with wall color.

Adjacent room colors factor in after you figure out what hue family is going in the LR - for example, we consider the Chroma (how muted they are) of Saybrook and Oxford and that helps refine exactly what color from the right hue family needs to be in the LR.