We sold our spotless downtown condo—cleaned top to bottom. Our two tidy cats never made a mess. Three weeks later, the new owner wrote: “We smell your dirty cats! Total mood killer. WE EXPECT $10,000.” I called our realtor, who said we owed nothing. But my wife had other plans. The condo was smart, and we still had app access, so she logged in, turned off the lights, then flashed them like a disco strobe. She adjusted the thermostat to freezing, then boiling. We heard back almost instantly: “What’s going on with the climate control? The lights won’t stay on!” My wife giggled like a kid who’d just pulled a perfect prank. I told her it was risky, but she shrugged. “He threatened us first.”