I have been thinking and sometime soon I want to get Chief a doggie back pack to give him a "job". There are so many I don't know what kind to get. I want to get one that can be worn often and not hurt his back. My plan would be to take it with us on walks and let him potty and poop on a regular walk. Since his main goal is to pee like crazy and keep trying even when he has no more left. My plan is when the backpack goes on potty time is over and its time to just walk. I know that part will take some training, but my question is what backpack would be comfortable yet not hard on him.