I was approached by a person wanting to help me set up a website. In order to do this he has requested that I allow him to transfer my domain name to his account, for easier management. I would retain the right of usage and he would pay the bill for maintaining the name. This sounds fishy, but I can't figure out what he hopes to gain if this is a scam. Is this a common practice among 'Administrative Contacts'?
If you transfer the domain, then you no longer own it and he can do whatever he wants with it. When your site starts bringing in traffic, he's free to cut off contact with you and profit from it. Even if he doesn't plan to scam you it's a bad idea because you lose control. You won't retain any rights unless he allows them.
It may be common in some cases (less tech savvy customers), but it's a bad practice.