When Charlie is first seen on the beach a stain on his shirts comes and goes multiple times. The very last shot shows some spilled sunscreen that caused the prior stain.
At the end of the episode, Dee is clearly seen taking Mac's bag and loading it into the vehicle. A moment later, Mac suddenly has his bag back over his shoulder and Dennis takes it from him and loads it onto the vehicle.
When Dennis and Dee are first walking along the beach one can clearly see the shadow of the camera on Dee's abdomen.