I'd rather climb narrow stairs under fire than be under fire in a lot of scenarios. Like a volcanos rim, while parachuting, walking out of the ocean with fins on(backwards), in a tree, with a straight jacket on, and while traversing a long drainage/sewer pipe. That makes climbing stairs at least seventh. So no i wouldn't set up at the top of the stairs unless you DON'T have one of the other scenarios available and if you don't you aren't well enough prepared.
$0 of an NRA membership goes to legislative action or court battles. Not a dime. Only money contributed to the NRA-ILA or NRA-PVF.
Of course, you could just donate to the Second Amendment Foundation
I was feeling pretty good, then I looked around and realized I am not swimming or on fire.