You can paint over existing interior wood finishes, if you take the proper steps first. Here's how. To paint over a stain, lightly sand all glossy surfaces until the finish is dull, then wipe it down with a damp rag dipped in de-glosser. Allow time to dry. Then with even strokes, apply a quick-dry primer-sealer to prevent bleed-through. Allow the sealer to dry, and you're ready for your finish coat.
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