The best advice is to hole up, . . . upstairs, . . . call the LEO's, . . . and hold your ground.
Personally, . . . I have a 1st floor BR, . . . but if I had my son's, upstairs, . . . and I knew bg's were in the house, . . . first thing I would do is get the swivel chair on rollers and get it near the top of the stairs, . . .
Bg starts up stairs, . . . meets chair half way or so, . . . also meets MBR while he is struggling with a 65 lb chair on wheels coming down on him.
I figure with either 20 or 30 MBR rounds and a 65 lb chair, . . . plus maybe a dozen or so .45ACP's, . . . he'll be convinced to go elsewhere, . . . if he is able.
Being at the top of the stairs is why it is called taking the high ground. It is a positive advantage, . . . only lessened if the bg can shoot up toward you through the floor.
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!