I have a friend who is a dealer
Why do you believe your friend is a dealer?
He makes a lot of money from it. It's easy to make money for him.
Its unwise you be friends with someone who is involved in illegal activities. If you're associated with them you may be forced to get involved if anything happens to them on a legal level.
I doubt his stuff will bounce back on me.
You don't know that. What if he hid drugs at your place or in your car? Just be on the safe side and cut ties with him.