At HD distances, . . . a long gun can be more hindrance than help, . . .
And a laser sight is a "dead" giveaway as to where the bullets may come from.
The best "plan" is to hole up and call the mounties.
Barring that, . . . plan # 2 to make the BG come to you, . . . get him in a shooting alley or funnel of death, . . . and take him down. Most quality handguns will suffice in the normal hallway, . . . stairway, . . . bedroom doorway, . . . and we are not talking much over 7 to 15 feet.
Additionally, . . . have the area back lit if possible, . . . it outlines the BG so you know what/where to shoot.
Be on the floor, . . . behind the bed, . . . behind a chest of drawers, . . . leave only enough of you out to be able to do the shooting. ID your target, . . . and make your decision.
May God bless,
If you can breathe, . . . thank God!
If you can read, . . . thank a teacher!
If you are reading this in English, . . . thank a Veteran!