Hi Whitefeather7,
Welcome to the Forum,
I would definitely hold off living together. How often does he drink? In my experience the two go hand in hand. I would say that taking cocaine is a problem even if it is only once a week, that can change in an instant.
You obviously have doubts and I would have a really good think about what you want for yourself, because living with an addict is hell. Sorry to sound harsh but I am just being truthful.
Take care.
Dx