So... DH put in our higher offer (in quite a grumpy tone) but then we decided that we should have another quick look at the house (from the outside) and speak to the NDN. The NDN was very nice but also very honest. They hate living there because of two enormous issues. They're basically waiting for the house next door to sell so that they can put there's on the market and leave.
One thing is that there is an ongoing legs, dispute between the house owners and the developer over the build quality of the homes. There's an issue with crumbling brickwork because the builder used the wrong type of bricks. The build quality is generally bad and they've had to replace a whole central heating system (boilers and all the radiators) and there are other issues. These are recently build houses, so the boiler should not have needed replacing. So we'd be inheriting a legal dispute (the issue also affects the house we were looking at, and once it was pointed out we could see it) and may have dodgy heating (the house was absolutely freezing both times we viewed so we're wondering if it's already broken).
The other issue is worse because it's about ongoing neighbour disputes and the position of the house. It's a pair houses close to each other next to a grassy area. Local kids use the grassy area as a play area (we were aware of this and its kind of why DH wanted to speak to the neighbours). The area is used all the time and the children are very, very noisy. They play football and there have been issues with balls hitting the houses. The kids (up to 15 a time) play there unsupervised any time it's not raining and are out until 8-10pm (depending on the time of year). You can hear them inside the house (we went after school when they were playing, and it's not quiet). The parents are apparently of the middle class 'benign neglect' school of parenting, and their parents have no interest in not sending them out to play loudly outside other people's houses. The NDN seemed at the end of his tether about it all.
We figure that even if he's exaggerating this (since you tend to build up ongoing issues in your head over time), it is still genuinely a bit of a problem. And it's exactly the sort of thing DH would get worked up about. The NDN said that the estate itself is lovely, it's just the position of these two houses that's the problem and that he's dreading trying to sell his.
So, yeah, we decided that we had to withdraw the offer and keep looking. There's nothing vaguely suitable to buy though. We are very despondent indeed and have decided to do a bit of a personal letter drop to see if anyone is interested in selling but hadn't realised there might be interested buyers, which will probably be ineffective but we can't think what else to do. 