@Gaz, I am in just that situation now. When we purchased this property we had it surveyed first. There were flags and pink paint everywhere. This had been a 60 acre farm that was divided into 30 acres (more or less) and the boundary lines went beside several farm buildings and right through one.
The neighbor with the house and barn showed us where the pipes were buried, front and back. It looked to me like the road spike marker was further into what he considered his land than the pipe, but DH said to forget it and take the pipes as property land. Who wants to move into a property and start a range war right away? Not us.
In 1997 we had the line between us re-marked (surveyed) from pipe to pipe as we begin clearing out that area. The neighbor had no problem with the markings. Then two years later he sold his property. We wondered why they didn't get it surveyed first, but it wasn't our problem.
When we reached the property line on that side with our cleaning and clearing, the woman came over in the dark of night and tore out a stake we'd put on top of the surveyor's stake to strike a straight line. That's when we realized she didn't know where the property lines were.
Being a teacher, I figured she just needed some visuals and explanation so I ran off copies of all our records and maps. I took the over to her one day. She yelled that she wanted her privacy and we were cutting down her property!
She insisted -- her friends had said -- we couldn't be closer to her shed than 8 feet because that was the law. I told her that we had once shared a shed with the neighbors because the line went through it until we tore it down together.
She insisted that the small fenced in area I had once put up around our (now gone) shed for winter pasture/shelter for my horses had to be the property "fence" line. Why? Because that's what she had thought (or wanted to think) -- even though the fenced area was small and rectangular.
So here we are 16 years after these new neighbors moved in and we are answering attorney letters regarding the property lines that are asking us to quit-claim 15 feet over to them. That is 15 feet -- 0.5 an acre -- from front to back even though, to my knowledge, no one ever questioned the pipe at the rear of the property as being moved or wrong.
I wrote back to their attorney citing the State's
Adverse Possession laws as simply as I could, explaining 37 years ago that
a. we were told this was our property line by the prior owner,
b. we paid taxes for this property, and
c. we had used this property as we wished for all those years. That should have covered even a mistake in the survey done for us before getting the property which is unlikely since the same surveyor did both parcels.
It has been over two months with no response, but I'm still not sleeping well over this problem. It is a whole other story I could tell about being neighbors, but that isn't pertinent to the boundary situation. If I had not kept all those records -- along with my fantastic memory -- who knows what might have happened. DH doesn't remember anything related to our early days here on our new property.