Here's how to make a DIY litter box furniture cabinet for your cats to help keep the litter and odors contained! StuffedSuitcase.com
This sofa saver. -- OMG, I need to make these!!! Luckily I know how to sew, and I have some heavy-duty canvas that will serve as a good base.
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DIY cat furniture, IKEA hack: TRENDIG 2013 tray table with cushions made from GURLI throw. Huge sisal mouse from Zooplus. Edit: GURLI is not cat-proof, so make cushions from stronger material :)
DIY Cat Tree
Window Cat Walk Shelf