Our first house was doer-upper, a mid-terrace of four in a nice leafy area. We initially got on really well with all of our neighbours, including the slightly batty, rather prim and proper old dear next door who fancied herself as the preeminent local historian and kept inviting us round for slide shows of the local neighbourhood.
After a couple of months we'd succumbed to this and spent a spectacularly unenjoyable evening with her showing us really boring photos allied to an even more boring commentary. We were there for hours......
Within a day or so she was on at us about another showing, saying that what we'd seen was about a 20th of her collection. At this time we were in our 20s, and if we weren't out socialising, we were spending all available time doing up the house. Consequently we kept giving reasons why we couldn't possibly go round again, but with a vague promise that we would again 'soon'.
Relations remained very friendly, particularly with her husband who was a poppet, and extended as far as us doing some shopping and minor DIY for them. However, after about 9 months of weekly invites, the penny finally dropped with her that we weren't going back again. Big mistake!
Overnight she became a nightmare! Complaining that we were making too much noise (which we weren't), that we were illegally occupying part of their land (they'd sold it to our predecessors), that our shrubs were encroaching their garden (no!), she reported us to the Local Authority about an illegal structure in the garden (shed, smaller than theirs, and no planning required), claimed that we were working illegally from home (not!) etc.
It came to a head when we replaced the old broken fence that divided our gardens. She was adamant that we were going to attempt a land-grab and try to 'steal' a few feet of her garden, and so she spent literally the whole day staring out of her window or out in the garden peering over the fence. She kept giving the fence-builders 'constructive' advice, until they phoned me up in desperation and asked what to do. I told them to move the fence to 1 foot inside our clearly delineated border so that there could be no suggestion that we were encroaching. Still that wasn't sufficient, and after another few hours of being monitored and berated at every move, the gaffer told her to 'eff off' in no uncertain terms.
The sh!tstorm when I got home was unbelievable, and was so outlandish that I found it funny. This was clearly not the reaction that she was expecting.
Ultimately this was the last piece of work that we did at the house and, as always intended, we put this on the market shortly thereafter and moved away.
Remarkably we continued to receive Christmas cards from her lovely husband until he died 10 or so years later, for what must have been a blessed relief! I bet she was incandescent when she saw our cards addressed solely to him!