The first thing you do is drive around the whole city taking pictures of every trailer parked "illegally". Present them, one by one, to the city council. Ask why YOU are being singled out. Show them a detailed plot map of your property, with elevations, so they understand what you would be up against if you decide to locate it in the rear.
I was told I could not install vinyl windows in a home in a historical district. I showed them over 100 pictures of similar homes in the area with replacement windows. I won my case, easily, saving my customers over $5,000 in the process. Who says you can't fight city hall?