if you have a drill already just grab a jigsaw at lowes, hd, menards, etc. Trace out your 6 inch diameter hole with a drafting compass (about 3 bucks at walgreens, office depot, etc.).Use a 1/2" drill bit to make a hole and use the jigsaw to cut out your circle cause that 6 inch holesaw is expensive. if you want to spend the 70 bucks, feel free, the right tool for the job is always best. You can get a cheap jigsaw for about 19 bucks.