Do we need to declare this when selling?

Section62

https://forums.moneysavingexpert.com/discussion/comment/82141671#Comment_82141671

You are taking a narrow interpretation of the OP's question though, and passing over the part where the OP said -

Just to fully paint the picture of this man, he's also racist, smokes a lot of his produce (the smell comes through into our house every now and
then) and is very loud (both just his talking voice, music, and a dart board on the party wall).

The current police activity may not be something which needs to be declared in itself, but forms part of a bigger picture of activities that certainly has the potential to "lead to a dispute". The dart board on the party wall and loud music would be enough for many.

jimi_man

https://forums.moneysavingexpert.com/discussion/comment/82141767#Comment_82141767

I'm interpreting the question that the OP asked instead of giving answers to questions that they haven't asked.

Being racist is not a criminal offence, and also is not something that needs to be declared on a TA6 form. Lots of people have questionable views - the line between nationalism and racism is somewhat blurred and there are certain political parties where this type of view is somewhat common. (I'm being careful to avoid breaking MSE rules). If he's not breaking the law then whilst distasteful it's not a neighbour issue. If he's shouting racist remarks from his window to people outside then that is an offence and also it's impacting on the neighbours and that may well be something that the OP might have to consider declaring. However the OP was at pains to point out that they've 'never experienced any direct antisocial behaviour and have no actual conflict with him'.

The fact that he smokes weed is also not something that needs to be declared on a TA6 form.

The noise issue can obviously be an issue but to reiterate, according to the OP 'we've 'never experienced any direct antisocial behaviour', so one must assume that it hasn't caused a problem to them. In which case it's not something that 'might lead to a dispute' and again, something else that doesn't need to be declared on a TA6 form.