This power cutter could be useful for both big and small projects. You will need access to an electrical outlet, but mains-powered tools have a very stable power subbly.
From Data Powertools
Metabo MFE40 110V, 1700W, 40mm Wall Chaser c/w 2x 5" Diamond Blades
Powertool World
Metabo MFE 40 1700W Wall Chaser 110v
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