How to cut out a rotted portion of exterior corner vertical trim?
This is a great project for an oscilating multitool.



The front blade (and there are several to choose from) oscilates from side to side in small strokes, allowing a precise cut in both depth and width.

There are corded and cordless models availble in a wide price range. Almost all would suit for your type of project. I think you will also find many other uses for the tool, making it a pretty good DIY investment, even for a beginner.

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