Dewalt 1 Speed Cordless 20 Volt Cutting Rotary Tool for Drywall.
Tool-free bit change allows for fast and easy bit changing - without a wrench. 26,000 RPM motor provides more cutting power. Dust-sealed switch protects against dust ingestion for longer tool life. Bright LED light illuminates dark work surfaces for accurate cutting. Great for cutting out electrical boxes, plumbing penetrations, lights. Included is a bag, 2 batteries and a charger as well as a target magnet for electrical boxes. You install one into the blue box, hang your drywall, come back with the magnet identify where the box is and cut it out. It works perfect every time.
I might be able to offer a bit or two but you will want to purchase more for yourself. They are break easily when not used properly.
https://www.youtube.com/watch?v=f1qNk6y9thA