W-man has a very good point. If much of the property is steep and rocky, you probably don't have a lot of grazing time on it.

Are you planning to build or spend significant time there? A fence could be useful or even necessary then.

I suggest settling in and talking to the neighbors;get a feel for their customs and attitudes. Their friendship and good attitudes may be worth far more than any value gained by keeping their cattle out.

Based on what you have stated so far, you could be dealing with a variety of situations, so it is hard to give any specifics. I do feel that there is nothing much worse than heavily grazed land, complete with cow pies, etc.

I also have found that some of fairest, most decent people I have known and dealt with are ranchers. Be decent to them and they will be decent to you.

I see you were answering some of my questions,even as I posted them; If you are rebuilding an existing fence, that is a different story. A brand new fence would probably require a surveyor to establish the legal boundary on the ground. This may not be necessary for an existing barrier.

I have never build any significant amount of fence, especially barbed wire, but I can assure you that it is a lot of work, but you probably already know that - good luck!