Neighbors illegal addition requires them to access my property for maintenance

[Christopher Russell]

I purchased a beach cottage on the East side of A1A in Palm Beach County Florida back in 2006. When I purchased it the previous owner made a comment that the neighbor built this room addition which was built right on the property line and he was not in approval of it, but never made a complaint. I was so excited to own a single family home with actual property on the East side of A1A that there really wasn't much that could have prevented this buy. Since then the neighbor and I have had several disputes, one which ended up with me calling the authorities to advise the woman that she was not permitted access on my property. This person is not particularly sane to say the least. The bottom line here is that I do not want to allow my neighbor to create an implied easement or a prescriptive easement because she decided to build an illegal addition onto the property line without taking into consideration that eventually she would be required to maintain the home. I do not want to contact the county zoning and start a huge fiasco resulting in her having to tear down the addition that has been there for 10+ years; I just want to cover myself legally so that I do not have to provide my property as access. For instance, if I ever want to sell the home, I want to be able to note that there is not an implied easement or a prescriptive easement etc.

All that being said, I am trying to find out what the best path of least resistance would be without getting into a Hatfield and McCoy situation.
Options:
1) Post a trespassing sign (this is a no brainer and I will do this immediately)
2) Create a document stating that I will not allow a prescriptive easement for access of the property, nor an implied easement and record the document under my address with the county?
3) Post a small sign that says no trespassing and also says owner of property will not allow a prescriptive easement or implied easement or any type of property access without written approval?
4) Send a letter from my attorney which will result in a massive blown out fight with my neighbor which I want to avoid at all costs.

If anyone has had an issue like this and can help that would be great. I really would prefer to keep code enforcement out of the picture, and would like to handle it myself, but ensure that I am covered.

Thanks to anyone who can help =)

Chris