Whats the Movie where a girl is locked in her house with a killer?

Only part i seen was a girl and her brother are locked in there house and they cant get the doors or windows open. then her (boyfriend maybe?) comes in the back door but when they check it, its also locked. After trying to break the gl on the windows a nother guy appears on the steps, obviously the bad guy. He get punched twice by the boy friend but it barely fazes him, then he takes a hammer from his belt and kills the boyfriend and follows the girl up stairs where she locks her self in a room, he slowly starts to take the screws out of the door but at the last sec looks at his watch and leaves. it shows the father of the girl in town talking to a man about the work he had done to his house and saying how that worker they sent was a hard worker. then the employer says we never sent any one to your house