Seems like every time I put the head rests down I have a need to ,put a person in there, usually have a blanket over back seat and console so my Westin can travel back and forth from front seat bed to back seat. As for the door. Pocket I fold up a couple of spare leashes and mini binoculars.....in the back I put a water bottle for long trips with my puppy ( under seat is no spill bowl).
For quarters that I use at the spray car wash I have two of the G M ash trays with the spring lid, put a plastic baggie of quarters inside each, fold down rear arm rest and place the ashtrays in the cup holders, put the rest back up and $10 in quarters disappeared.