I employ the “breaking glass” rule.
After hearing breaking glass, you can shoot any damn person you find in your house.
If you didn’t hear breaking glass, you’re probably best not to shoot.
A 3AM, wrong address, a$$h++e, loud mouth, drunk, late luggage delivery guy is fortunate I applied this rule when he drove his Pinto up our winding driveway to our rural home, and approached a ground level bedroom far from any entrance.
“A 3AM, wrong address, a$$h++e, loud mouth, drunk, late luggage delivery guy is fortunate...”
The one time I had someone in my yard at 3 AM, it turned out to be a drunk teen who lived two houses up. That would NOT have been a good time to shoot!
If someone tries to force their way into my house, or is obviously trying a home invasion with weapons, then it all changes. But even then, if I caught someone in the act of opening a window, I would wait to see if they were acting drunk.