Having chosen to stay with Sam after the battle for the Allspark, Bumblebee made arrangements to be close to him at all times. It's been a pretty good deal. He gets regular detailing, and as much high-grade fuel as he needs, plus he gets to spend time with Sam and Mikaela. His vocal processors still aren't fully up to snuff, but he and his friends communicate just fine. If he ever misses the action of battle, he can always give Ironhide a call and they can go Decepticon hunting.