We used to live next door to a couple in their late 60's who were both retired, we were in our mid 20's at the time. When we first moved in, they couldn't do enough for us, but after a while, it started to get on my nerves, as we couldn't go out in our back garden, without the pair of them coming out and wanting a chat and wanting to know all of our business.
The problem we had, was that the fence was probably about 3 feet high, so we had no privacy whatsoever, we couldn't even have a Barbeque, without the pair of them coming straight out of their back door and seeing what we were cooking.
We even felt like they were watching us when we pulled up on the front drive as well, as they had their sofa positioned perfectly and they would perhaps put their milk bottles out or go in the garage as we were getting out of our cars.
One day I had, had enough and I told them I wanted a 6ft fence put all the way along the back garden, they said it was fine, but they never really spoke to me again and we ended up moving.
I also fell out with an old bloke who had a bungalow that backed on to the side of the same house, he took exception that me and the Mrs started knocking nails in the divided fence between our properties, all we wanted to do, was to have a climber plant growing and he wasn't happy. A few days later, I managed to dig out the deeds of the property and it quite clearly stated that you can maintain your side of the fence, so I took it round to his house and showed it to him, he just stared at me with his bloodshot eyes and I told him I was getting pissed off with the neighbours round here, he never spoke to me again as well.
The motto of this story, is that old people have too much time on their hands, so avoid moving next door to them!