Note, this book was read before I got a Goodreads account as part of a challenge to read 50 new books by the end of 2019. I wrote a review for it right after I read it and copy pasted it here.
This was actually surprisingly good. My low expectations weren't really helped by my strong skepticism of ghosts (I'm not saying nothing unexplained or really weird is going on in at least some of the cases, I just don't necessarily believe that it's necessarily the souls or imprints of dead people) and the tendency of media to over-sensationalize any supposed hauntings. These came off as really genuine, though.
There were some pretty extreme stories for certain (for example ghosts moving things, regular full bodied apparitions that seem aware of other people, loud noises heard by entire buildings of people, children knowing things they shouldn't because they've been talking to grandpa who died before they were born...really impressive things. However, there's even more of the more subtle stuff: sensations of suddenly being dragged into the past, seeing weird hazes you just know are people, people that you know you saw but aren't there when you look again. In other words, possibly ghostly but not really flashy. Come to think of it, there are only maybe 3 ghosts that seem to have any violent intention towards their hauntees described in the entire book and even of those the worst that seems to have come of it is a flooded basement and some folks (mostly children) being frightened. If anything it seems a little under-sensationalized.
I think this is probably mostly because Boye got his stories by putting out a newspaper ad requesting people contact him with hauntings rather than just reporting/overhyping the few well known ones and then sticking to what people described. This, combined with knowing a lot of the places referenced just makes it feel more believable.