Here are a few things that I think make these spaces so successful:
1. Keeping the walls a light, off-white color. While true white can be a little harsh, choosing a slightly warmer shade of white or another light color makes the room feel large but cozy at the same time, and gives you a blank canvas for decorating with bright colors.
2. Use bright colors as accents. The pops of colors in the art and furniture are wonderful. Also, a fresh coat of bright paint is a great way to take an older piece of furniture and give it new life. In one photo below a simple wicker table is reinvented with a coat of bright pink. In another an antique wooden chair brilliantly stands out with a coat of bright green/yellow.
3. For artwork and rugs, mix modern with antique. Place a large, colorful modern canvas next to antique framed black and white prints. When hanging frames next to each other, keep one common element such as the general color of the frames (i.e.: all dark or black), but select different frames, some square and some round, and hang at different heights. Etsy is a great place to find relatively inexpensive art, and you can get cheap frames at Michaels. For rugs, try Ikea!

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