A 3-In-1 Box Jump is a great piece of equipment that doesn't take up a lot of space and adds a lot of versatility (Box Jump, DB Step-Up, Push-Ups, Dips, Box Jump Over, etc.)
The dumbbell is probably the most useful of all items to have at a home gym. With only 1 dumbbell you can get a full body workout to be healthy, happy, fit. But... eventually you will probably want to get a set, or a few sets.
Use in your warm-up to get your body loose, use for your rest days to recover, the foam roller can help you to stay healthy and feel good so you can crush your workouts and live healthy!