Also, with regard to Washington State at least, you have to show a clear and articulable threat to your person, or the person of another.
There are plenty of different laws and statutes concerning the use of deadly force. The best and safest way I have found to go is this:
For property alone, I would NEVER use deadly force. Let them take what they want. So, the neighborhood thug is running off with your prized possessions? So what? Let them have them.
I believe that someone who posted earlier asked if someone would feel comfortable taking someone's life over a piece of property. I sure would not. The only property I would actually consider using deadly force to stop from walking out of the door, would be firearms.
Now, if when the perp enters, they have a visible means of inflicting great bodily harm or death, that's a different story. For instance, you happen to see Mr. Burglar enter through a sliding door. OK. Scare him off, turn on the lights, or perhaps challenge them--at gunpoint--instructing them to lay on the floor. So far, so good.
If they turn to run, LET THEM GO!!!!
If they start toward you, all bets are off.
If they enter the house, and a deadly weapon is visible, all bets are off.
If you see said burglar who, after rummaging through the common areas, starts to enter the bedroom of one of your children, all bets are REALLY off.
But, not for property. Never just for property, except operational firearms.