(Notarized and registered)
"Dear neighbor,
I just wanted to follow up on the brief conversation we had on xx/xx/xxxx.

As mentioned, I have recently noticed that you have been installing outdoor lights at xxx location. It should be restated that in accordance to the deed/plat/survey/x that this property belongs to myself, and that this construction was unknown and unwanted to myself, previous to it being started. At this time, this usage of my land is considered encroachment.

In the interest of being and staying neighborly, I would like to extend the offer to lease this limited area of land provided that it be maintained to the highest standards, that no additions other than existing (lighting) be added, that it be maintained to conform to all state/county code requirements, and that you assume legal responsibility for it's upkeep.

Please sign and return the following within 30 days:
Attached Lease (revokable upon lease violation) $1/yr/xyrs.
Attached waiver of liability

It was nice to meet you, and I would like to remain on good terms and blahblah, however I need to protect my interests. I hope you understand.
Thank you xxxx"

You don't lease the land to him. You license him to use it. He gets a license to use it free of charge with the recognition that you own the land and can revoke the license at any time. This is what preserves your land from an adverse possession claim. In the meantime he can use the land forever at no charge and without either of you caring. The license can say he maintains the property and can use it or not as he sees fit as long as he doesn't damage it. That's it. Nothing more.

Do NOT send him a registered notarized official legalese-filled letter unless you want him to shut down completely and treat you like an adversary the rest of your relationship.

The problem here is that he never dreamed of taking your land through adverse possession and probably thought that you would appreciate him dressing up the place. Next thing he knows you're dropping words like adverse possession and do you know I own the property and he freaks out because he doesn't known what to make if it.

Next time you see him you tell him that you handled the last conversation badly (you didn't, he reacted badly but it goes over better if you say it that way) and that you didn't mean to upset him. All that you meant was that if someone else uses your land for long enough you can lose ownership of the land and you know that neither he nor you want that. So to keep everything orderly, you're happy to let him keep doing what he's doing, but you need to give him a license to do it, so that the two of you don't inadvertently transfer ownership through adverse possession. If the speech has gone over well so far (judging from the expression on his face) you can plow on and say that as consideration for keeping the land in nice shape, you expect to get together and buy him a drink at least once a year, and that in consideration for the license to use the land you expect him to buy you a drink at least once a year.

MRM is spot on...(again) :)

I read the meeting to be: "Yeah I'm using it now, bugger off you're annoying me, and if you don't disagree in writing now then it's consent from this point forward".

The correct response should have been: "Howdy, sorry I didn't ask before but I wanted it to look nice, thought you wouldn't mind, nice to meet you."

With nothing written how does he prove it if things go south sometime in the future?

I smell spam...

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