You can definitely use a hand mixer for cake batter and buttercream.
My essential cake decorating tools include a turntable, cake scraper, straight icing spatula, offset icing spatula, cake boards, and three 8×2” round cake pans. Those are my essentials, but I also love having a cake leveler, cake lifter, piping bags and parchment. You can shop my favorite products below!
I got mine from a company called @cakesafe but many of you have told me you have found similar ones on Amazon