When my son was 7 he had a hairless rat. She was really neat but already an adult as we aquired her from a school. She did not smell at all. We never got her a buddy but my son played with her daily and she was extremely friendly never bit, loved to snuggle. Called her name and she came out of her little house every time wanting to be held. Rats do not live very long as I was told by the vet, three to four years if you are lucky(Molly developed mammary cancer and had to be put down and she was only about 2). Also I was told males usually bite? Never had experience with a male so cannot verify that. Tell him to get one really young so that you will hopefully have more time with it. They are capable of being trained to do many things, as are mice. I had mice many years ago. They made just as good of pets as Molly the rat did, just a smaller version and a little more hyper. We cleaned Molly's tank out every couple of days. Don't use cedar either, vet said that it causes upper respiratory infections in most small animals.