When choosing colors, remember it always dries differently than it looks.
Always! Paint store samples are sometimes close, but often not.
My bed room is red below, very light yellow above, with a white ceiling. My massage therapist was going to do the brush work, so we went to the paint shop together. She wanted to use rust reds, orange reds, wimpy reds, and assorted other girly reds. I wanted a red red.
I found the red I was looking for on a package of low budget Nylon brusheswhich stayed at the shop, by the way: you couldn't pay me to use anything but a top quality bristle brush. I asked the fellow behind the counter whether he could match that red. It's a medium-deep cherry red, very round, very warm. He said he could. She was appalled. The red on the walls almostnot quite, but almostmatches the red on the package.
I ended up with my red red. It's a north-facing room with a single unlarge window. It's gone from a dark to a light room, a room that felt chilly to one that feels warm.
Make sure you get your colors instead of somebody else's. If your paint store guy can't mix the color you want, go to another paint shop: there's not exactly a shortage.