You can't actually report a rental loss on your tax return unless you are renting at fair market rates. Unless he pays rent at fair market rates (what you would charge a stranger to rent the same house in the same neighborhood in the same condition) there is not much financial advantage to renting.
If you simply gift him the house by quitclaim deed, there are no taxes owed by you, unless your lifetime total of gifts is more than about $15 million. You would have to file a form 709 gift tax return but no tax is owed. He would also receive your cost basis (what you paid originally, plus what you and he have paid for permanent improvements.
The only concern I know of, is that if you require long term medical care and apply for Medicaid, Medicaid can claw back gifts made within the previous 5 years. I'm sure there are other ramifications of giving him the house vs renting it to him at cost.
If you are renting at fair market rates, then it is probably slightly to your advantage to continue renting, unless you or he just want to put the house in his name to avoid entanglements.
