When we bought our first house, we got a free puppy. Free puppy = $900 fence in back yard. I had the fence company find the survey of the neighborhood, found the corner stakes, and then went to talk to my neighbor.... you see, he and I had always agreed that the line went from a post back in the alley where our trash cans were, out to the street. However, the corner stake was 6' past that post and actually under the corner apron of his garage driveway to the alley. The property line was 6" (inches) from his garage. If I'd put the fence on the property line, he'd have just 6" to get to the side of his garage. He'd never be able to paint it, fix a broken window, trim along the side, etc.... plus, I really liked the neighbors. Older couple that really treated us well. So, after showing him the property lines, I told him we'd put the fence 3' into our yard so he could still get to his garage sides, mow along it, etc... and we'd keep his trash cans on my yard at the back. I poured a nice pad for the trash cans, too.
In the end, he ended up mowing our side yard for us in summer and I'd clear the alley, their driveway, and their front sidewalks of snow in winter. He'd take me fishing, and we'd go for Sunday drives with them once in a while. Our wives would bake each other pies, and we'd sit on their garage porch and drink beer and cocktails with them. We had 10 good years of friendship until he passed away.
I think it worked out because he wasn't using my property in hostility and they liked our free dog. We came to a very good compromise for both parties. But that's city living.... tight quarters, you'd better get along.
Good luck to the OP. I hope he gets his survey, and that the neighbor doesn't have access to a good-old-boys network in local government that'll make it drag on for eternity. Fingers crossed. :thumbsup: