UGH! Neighbors!

So my "new" neighbors are building a storage barn or something like that in front of our garage, our land is laid out very weirdly. Our garage looks like it would be apart of their yard (Yes, they know it is our garage though)

But anyways they came over to my house and asked about some of my house wires that are in their way, no big deal they just hang low so they just need pulled up so they can finish their... whatever they're building, BUT the real problem is since our yards are set up differently I'm not sure of where our boundaries are. Well, when the neighbor had come over about the wires I had curiously asked if they had their land professionally surveyed, since I had been told by my step-dad that in order for us to put up a fence that we would have to have that done just to be safe. So the neighbor lady didn't know so she called her husband over who said they hadn't. So I informed them of what my step-dad had told me and it looked like they were going to stop building. They had torn down the frame they'd set-up, but today, which is probably about a week after telling them this, I wake up to someone hammering... the frame was once again up and the builder is still out there.

Now I'm all for building things, AS LONG as you know that it's on your property!

We had already had a problem with this couple where they were mowing part of our yard, which was dealt with when they came over about the cord. So I'm not really liking them at this moment. They're building this thing like 1 or 2 feet in front of our garage, which I would think would still be on our property so I finally called today and asked for an estimated price to get the land professionally surveyed (our property of course not theirs) Which they, the neighbors, should have had done before they started building anything.

We would have eventually had to get this, the surveying, done anyways for a fence, but now we're going to have to use our money to have this done now and then if we find out that their stuff is on our property we'll have to tell them to move it.

Now I would like to have neighbors that I could get along with, but they're making this very, very hard. They keep trying to take over. And if this leads to us having to go to court you better believe I'll do it, but I'll be ticked!

I can't believe that I could tell them what is necessary for them to do and that they would still not do it, sure I'm young, maybe they think I don't know what I'm talking about, but I'm not stupid, I have been around my step-dad for all but 3 years of my life who deals with this stuff a lot, so I know things. Plus you'd think common sense would tell you to make sure the land is your before you build something on it.

One of the other neighbors for some reason thought that a chunk of our property was the new neighbors and so the new neighbors just took their word..... UGH! All this annoyance is giving me a headache!