Here is my story from about a decade ago. I have to use a throwaway because I'm sort of required to keep some things confidential about my employers.
From the time that I graduated high school to the time that I finished nursing school I worked as a caregiver for a nice couple who had the husband's elderly mother living with them. It was a great job because it didn't involve much and paid very well. My mother knew the couple from where she worked and had set me up with the gig.
I had been working for them at least two nights a week, whenever they had dinner plans or had to go out of town for business. (They were both doctors but were employed by a pharmaceutical company) The elderly mother was very sweet and was a total treat to be around. She was often very tired in the evenings so we didn't spend too much time together, but when we did she'd teach me how to cook the most amazing dishes and tell me old stories.
The strange occurrences began on the very first night I spent in their house. It wasn't anything serious at first. Just weird sounds and doors that were open that I was sure I had closed behind me, stuff like that. The house was very old and I was sure that most of the noises and open doors occurred due to house's age and it settling.
One night while I was there (about three months into my employment) I was downstairs sitting on the couch reading through a textbook because I had a big test coming up. The lights were all dimmed except for the one I was using to read. The rest of the living room was in shadows. All of the sudden I got a strange feeling, like someone was watching me. I glanced up towards the darkness and thought I could make out the shape of a tall person standing in the distant shadows of the den. My eyes were so used to the bright reading light that I couldn't see much of anything in detail. I called out "Beverly? Is that you?" (That's the name of the elderly mother I cared for) I didn't get a response so I blinked and rubbed my eyes. They were closed for just a second but when I opened them the figure was gone. I felt very creeped out but I knew it was just my eyes not adjusted to the darkness.
When I was done studying I got ready for bed. I was allowed to sleep in one of the smaller guest bedrooms that were down the hall on the second floor. It used to be the bedroom of the husband when he was a little boy. I had put my books back in my backpack and set them on the table in the den, then went upstairs quietly so I didn't wake Beverly. The second floor is set up in a long L shaped hallway with doors to rooms on all sides. At the end of the first length where the hallway bends to the left there is an old mirror hanging on the wall.
As I was walking down the hall I momentarily glanced in the mirror as I passed it and there was that figure standing behind me at the end of the hall. This time it wasn't my eyes or a trick of the light. There is a small lamp at the bottom of the stairs that always remains on so that anyone moving around at night doesn't trip down the stairs and break their neck. It casts light up the stairway and illuminates the green wallpaper at the end of the hall. The figure was a very tall silhouette of a man standing at the far end of the hallway I had just came from. (All of this was realized in a second) I screamed and turned around to find nothing was there. An empty semi-illuminated hallway.
My scream woke up Beverly cause I heard her calling for me from her room. I walked cautiously over to her bedroom door and went inside. Beverly always slept with a small lamp on at the end of her bedroom, so I could see her clearly when I went inside. She was sitting up in bed and she asked me what was wrong. I told her it was nothing, I was just startled by something. She looked at me what I believed to be a very weird question at the time. "Was it something inside the house or outside the house that startled you, dear?"
I thought that was very strange and I asked her why that mattered. She told me that it was important and asked me to please answer. I told her it was inside, I thought I saw a man in the house. She instantly looked at ease and told me that it's okay, it's just a trick of the light.
The next morning I couldn't stop thinking about it and what she had asked me. I assumed that either I was going insane (which wasn't likely) or that Beverly was experiencing some dementia (which could be very possible) and I should bring it up to her son and his wife when they returned.
Once they had come back that evening I asked to have a word with them. We sat in the den and I explained that I had been startled by something and that Beverly had asked me the strangest question about it and then seemed to have a strange emotional flip flop when I answered. I told them I thought it might be a sign of a change in her mental status. The husband politely told me that his mother is not crazy, not going crazy, and very much sane. He told me that she was considering my best interest when she asked me what frightened me.
I felt bad suggesting it because it seemed he had become defensive. Immediately his wife saw that I was misreading her husband and spoke up. She told me that Beverly knew something I did not, which is why she asked me that strange question. They both reasoned with me and explained that they believed their house was haunted. I seriously thought they were joking, I even laughed. They did not laugh.
The husband explained to me that strange things have happened around the house ever since he was a kid. The house was built by his grandfather, Beverly's father. He explained that he had done his research and as far as he could tell no one had ever died in the house. His grandfather and grandmother both died in a car crash together, Beverly's husband died in WWII, and not even a family pet had died in the house. So there is no traditional reason for the house to be haunted.
They explained that the weird occurrences in the house are the reason they pay me so well and allow me so many freedoms around the house. I hadn't thought of it yet, but Beverly was a very active elderly woman to warrant someone being paid \$100 a night to watch her. Especially since I wasn't a medical professional. Not that Beverly needed a medical caregiver. He told me that I should talk to Beverly about it.
I spoke to her later that week. She apologized for not telling me sooner but they all thought I would turn down their offer if they admitted that the house was haunted from day one. She explained that there are two rules I needed to understand. (I had never heard of a haunting with rules) She told me that if I see something inside the house it might seem scary but it can't hurt me, it doesn't mean me any harm. But if I see something outside the house, like outside the window, then I should stay away or go hide.
That scared me. She told me that often people will see a tall man inside the house. She said that no one is sure, but said she thinks she knows who the man is. She took a framed picture out of her drawer and showed me. She asked if that looked like the man I saw. (I had never told her I saw a man in the house) In the picture was a very tall man standing next to a woman of average height in front of an old car, probably brand new at the time. It was hard to tell if that was the same man, but the height and the shape seemed right. She told me that the man in the picture was her father, the man who built the house. She told me that he is the only figure seen inside the home. But outside the house there is another figure, a thin man who is of average height. He is seen standing in the window, on the lawn, or in the trees off the property. She told me her dad keeps him away, keeps him out of the house.
I saw many other things after that, but the story is getting too long.