Cold rooms aren't a furniture problem, they're a materials problem. You can rearrange a grey-and-white room forever and it will still feel like a very stylish waiting area. What it needs is warmth you can see: wood grain, fabric with a nap, light the color of honey, and at least one thing that's having fun.
Everything below got vetted the same way my Pinterest picks do: real photography, reviews from humans who actually live with the thing, and a shape that won't embarrass you in five years.
Green Corduroy Chairs with Walnut Bentwood
Green corduroy on walnut bentwood, like a 1962 den and a very cool aunt had a baby. Light enough to drag anywhere, gorgeous enough that you won't want to. Dining chair, desk chair, or the corner chair that collects compliments instead of laundry.
Geometric Squares Area Rug, 5x7
A grey floor is a confession that nobody stopped it in time. This rug stops it. Warm geometric squares that read mid century without cosplaying it, sized to anchor a seating area, priced so you don't have to whisper the number to your partner.
Light Amber Glass Taper Candle Holders, Set of 3
Amber glass catches light twice, once at the flame and again in the base, and suddenly your cold room has a fireplace's worth of warmth in eight vertical inches. Run all three down a table or cluster them where the afternoon sun lands.
Melted Magic Cube Accent Rug
Every rescued room needs exactly one object that makes guests grin, and a Rubik's cube mid-melt is that object. Park it by the reading chair or at a doorway. It's the wink that tells people the rest of the room was on purpose.
That's the kit: something wood, something soft, something glowing, something fun. Notice there's no "repaint everything greige" step. There never is.
Want the method behind the four moves, including the order to do them in and the budget version of each? The full plan lives in How to warm up a grey living room. And if the chairs were your favorite part, there's a whole roundup of their relatives in Chairs Worth Fighting Over.