I'll tell you one of the things that happened to me.
Back in 1990-1991 I lived in a small room in my grandmother's house. My granfather was dead, and she, born in 1911, had me as a house "guest" for several years.
Anyway, she used to go on visits to her sisters in the capital etc, so I was often alone in the house. But not alone, since there was something there.
It was a very small house, basement and top floor, the floor being of wood. There was an entrance on both floors, at the same place, so that the entrance downstairs where I lived was ybder the stairs up, and they were joined with a steep wooden stairway (similar as in a ship) on the inside.
The house, being built in 1936 was as so many houses of that era, build of all sorts of scrap, - it was after all, short ways from the great depression, and material was scarce. And that means a small house (20 by 20 feet) and thin boards. Creaky floors, - I could always hear from below where in the house my grandma was, and which shoes she was wearing.
Anyway, I started observing that there was somebody walking upstairs. I would have guessed a heavy male wearing no shoes. The walking was from the living room into the kitchen, or from one living room to another.
At first I was startled and jumped upstairs, and there was nothing there. There was no chance of getting out, since the stairs left me straight at the entrance, and the door was locked, and a noisy one too.
There was an odd feeling about this, since I felt no hostility. (oh, I had some taste of worse "things"). So, I sort of got used to this "walking". The "walking also increased, and was at times a daily event.
One fine day, I had just arrived and was standing below the stairs, when the "walker" walked from the living room into the kitchen. I sneaked on to the lower platform of the stairs and grabbed the handrail, and I heard the "walker" again in the kitchen. So, in one leap, I hurled myself upwards, it was perhaps two seconds before I was loking into the kitchen, blocking the out-door with my back (in my position I could see them from where I started my jump thereby eliminating any physical exit). All fell silent. There was nothing there. No catch for me
Anyway, I got used to this, so I didn't really bother. That can not be said about other people. My dad used to come and stay with me, and he was startled at first, then got used to it. I used to have workers, and they shared the room with me, one of them got quite used to this ,but then there was one, who got quite uncomfortable about this.
He was a Danishman, a rationally thinking vetrenary student, and one of the best persons I ever employed. Being quite disciplined, he would always get out of bed an hour before the job, shower and shave and put some entry in his diary.
One fine morning, the "walker" went rattling all over the floor. Quite noisy this time. And the Dane asked me if my grandmother was back. I said "No, it's just the house-ghost". He was baffled with that answer, and after some more rattle, he went upstairs to investigate. When he came back, he was completely pale and in a state of confusion. "I don't get it, the door was locked, and there was no way anyone could have made it out, and the floor is empty". "I told you" I said, "you won't catch this one".
He was always quite puzzled about this, and will probably never forget.
Another worker of mine (who had gotten used to this) had a girlfriend. One rainy night, the girlfriend went to some school party. We decided to find a party for ourselves, and ended up on a farm some couple of miles away. In the meantime, the girlfriend decided to make a short ending on her party, and went to our place.
The place was empty of course, except the "walker" was in a merry mood. She got scared out of her mind, and anticipating where we were, badly dressed, ran through the dark and the rain to the farm where we were!!!
Next day, my worker detected some triumphand footsteps above him.
I never found out more. The house has now been empty since my grandmother passed more than 11 years ago. People in the street have told me there is often someone there, looking out the kitchen window, then disappearing. I am not surprized, but I am always curious who this friend of mine was.
That was just one story, and honestly, this is absolutely true!!!