Watched several of those Youtuber videos of guys exploring old abandoned buildings, out of curiosity.
Here is my analysis of what they found. (aside from creepy music and hype, combined with jump-scares)
1. Imagination and fear. Many times they just freak out over a 'feeling' when nothing is really there.
(they have to find something, right? otherwise what is the point)
2. Old building settling/crumbling making noises as old buildings do.
3. Leaks. Water dripping/running here or there.
4. Animals. Wild/Stray animals love abandoned buildings.
5. Wind. Abandon buildings are open to the elements in several ways, with seen and unseen openings.
6. Homeless people and or drug addicts. Many times the 'haunting' is just some guy or people using the place for whatever.
I would be more afraid of someone actually living there than any 'ghost'. That is the real danger. Also, the roof collapsing or the floor caving in are real concerns. Bottom line: Going into old abandoned buildings is dangerous but not for ghosts. Animals, Bad People, and Structural Issues, are much more reality based 'dangers' than is any phantom. Anyone doing this should certainly be armed and should have a safety backup nearby.
