The interior knob on my front door needs some serious help. For six months now, the knob has been coming off the door when pulled in a certain way. So every once in a while an unsuspecting guest pulls on the knob and the whole thing comes off leaving a brown swipe of grease on their hand, or worse, their clothing. I have absolutely no idea how to replace a front door knob and lock, nor does my husband. I may have to call someone in.