First off, Barbara, I wouldn't invite those neighbors to my next bar-b-que get together in my back yard. Neither would I send them a greeting card on holidays.

Don't mean to be flip about a serious problem, but there may not be much you can do other than not having any future contact with the neighbors. I don't know what size city or town you live in, but most cities are getting pretty strict on things like this. It wouldn't solve the neighbor problem of course, because things will never be the same now between you and them, but is there some other nearby area where you could park the vehicle? If so, then do so, and buy a rusted out old Volkswagen, as ugly as you can find, and park it as close to your structure as you can and still stay within the zoning limits allowed.

Too bad things like this happen, but unfortunately they do.

DougR