There is a famous (among first year law students) case[1] that seems relevant given the nature of the issue is one a buyer would not reasonably be able to ascertain on their own. One possible point of differentiation: ghosts are a permanent defect on the value of the property while loud children living next door would probably only torment the homeowner for a decade or so at most.

The opinion is famous not just for its unusual fact pattern but also because the Judge clearly had quite a lot of fun working in other-worldly puns and references while writing it.

[1]https://en.m.wikipedia.org/wiki/Stambovsky_v._Ackley

Yes, and even if something is super annoying, it might be legal. For example they listened to music until 2-3 in the morning a lot of cases. Thumping reggaeton. And while it for sure wasn't over legal limit by decibel, the bass made my bed shake.

Yes, you'd have to be prepare to counter that with e.g. testimony from neighbors, or friends who heard the previous owners complain. It's not a slam-dunk, but it is an actionable tort.