Here is a balance & core trainer that helps you burn calories and improve your balance, coordination, and flexibility while targeting your core muscles. The DEVEBOR Balance Ball & Core Trainer adds instability to your favorite core workouts to push your body harder. It rotates 360 degrees and tilts 15 degrees, so you can perform front to back, side to side, and circular drills.
The DEVEBOR Balance Board lets you perform planks, hip raises, crunches, squats, and other common moves. It can handle 300lbs of weight. Costs under $60 at this time.