"Never sell no crack where you rest at": I think you misunderstand this one. What he means is that you should do the risky stuff somewhere else, where you can step away from.

Your home is where your family is, where you are vulnerable as you sleep, you don't want to do something like having crack-heads around there or cops busting down the door.

In technology terms, if you have something bringing in steady money, don't go do crazy experiments on it. If you have a project that needs to be delivered on a certain date, don't go using a brand new untested language on it.

In essence, do the risky stuff at a spot where you can walk away with little consequence.