I live in a row of terraced houses with a pavement outside the front of the houses and then a patch of grass on the other side of that which the council owns and maintains.

I live at one end and the neighbours at the other end have always had things on the grass outside. I've never been bothered before but lately it's been growing. It started out with a greenhouse and some large plants but they've now also put up a shed, a slip-n-slide and a massive pool (the kind that you need to climb a small ladder to get into). It's slowly encroaching down the street with stuff now directly outside their next door neighbour's house.

I appreciate it's a small problem to have but I think I should say something because:

• It looks very unsightly and offputting for anyone trying to sell their house in the street. As a prospective buyer I'd just think "if I move here I'll have an inconsiderate and entitled neighbour with no respect for other people's space".
• If nobody does anything what's to stop them doing it again next year or potentially adding to it?
• They're leaving large patches of dead grass. The slip-n-slide has already left a large strip in one place and now the pool will do the same but worse.
• Unlikely but there's a potential safety issue. They've left a large deep pool unattended for days at a time with a ladder allowing easy access. It's right beside a popular bridle path / walking route used by families with small children.
• I think it's just a very entitled thing to do. They have back gardens like the rest of us. If they don't have room for a pool and a shed maybe they just shouldn't buy them.

I'm hesitant to say anything as it's not really affecting me right now and it's certainly not enough to be worth it if I have to then declare it later. I get on quite well with one of the residents so I could try to have a chat about it but they're not going to change anything just because I ask nicely.