Creative suggestions but all go to the symptom, not the problem. Unplugging your heater is the symptom - the problem is that, for some reason, 3 neighbors are acting rather childishly towards you. I'd want to know why. Do you have a loud exhaust and odd hours so you wake them up early in the morning or late at night? Do you party hearty all the time? Did you accidently run over their cat? (These are rhetorical questions - please don't answer.)
Point is, if someone told you it's three people who are ganging up on you that someone must know who at least one of them is. Go ask what the problem is in a calm, rational, adult manner. You might find that this is all based on some misunderstanding that you can get resolved easily. Might even make a new friend in the process.