Bear mace disguised as body spray. Stun gun in bag. Boot knife. Pistol in glovebox for safe measure.

As soon as you step in you say "Hi! Would you like some gum?" and immediately start digging in your bag. This will confuse them as they ponder "who offers gum anymore?"

Rattle off the contents absently, lighter, lipstick, body spray... And then pull out the 'body spray' like you're just getting it out of your way.

Quick as a flash, take a deep breath and hose 'em with that shit. You want the face but start at the top of the chest and sweep up just in case they're paranoid and duck or jerk their head to the side.

Do not hesitate, don't wait to see how effective it is because that mace cloud will be everywhere including you. Hit them with the stun gun. A couple of times.

Don't take too long on the next part because they might have backup further in the house. Get their wallet and, the most important part, their keys.

Dip quick but don't run when you're outside, just play it cool.

You'll probably have at least a day or two before they change the locks. That's your chance.