Ouch! Those kinds of disputes are a really sticky situation. If they really wanted to park there, then they should have the decency to pay for it or at least move when told, without any complaints. Really though, they deserve to be towed, since they're parking illegally. Maybe you guys could bring it up to the proper authorities so that those neighbors from hell get what's coming to them.

Thanks for sharing your tale. It must've not been easy, so I appreciate it!