Here are some images of wallpaper-in-action, in case you need help visualizing how your pad will look all gussied up:
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Above image from Elle Decor. I cannot even describe how much I love the metallic paint dribbled on the wall. This will somehow be making an appearance in our home.
A friend recently brought up Fromental wallpapers (thanks Jenny!) See their wallpapers below, a great splurge - think of it as large scale artwork.
They have some really sophisticated color palettes
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These birds would also be great for a kids' room
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Some of their wallpapers have BEAUTIFUL, unexpected, bright colors.
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These wallpapers below are actually embroidered:
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They even show the overall layout of all the wallpaper panels
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If you can't afford an entire wall of a high end wallpaper but like the look, take a design cue from Jenny and frame a few panels like art, hang on your wall, voila!