With an adjustable weight feature, you can easily change weights to suit your workout. Also dumbbells are a great start to a home gym since it can hit multiple muscle groups with different exercises.
Adjustable Dumbbells
As long as it does the job, I think any brand will do. This is as essential especially for those floor workouts, stretching routines, and yoga sessions.
Yoga Mat
If you can't go out for a run and can't go to the gym to hit the treadmill, a skipping rope is that way to go to get that daily cardio goal!