In high school I had a friend that I'd end up crashing at his house on a regular basis on the weekends, when we first started hanging out he made mention of his house being haunted and I laughed it off but he swore up and down it was true.
Over the course of a few years of spending many weekends there I saw enough to make me a believer.
My brother was there also one day and was coming from the living room towards the kitchen and I hear him freak out and start running and then see me in the hall and he stops sudden on a runner rug in the hall and the end behind him bunched up like someone we couldn't see came to a sudden stop also. We both saw it and were like "HOLY SHIT!!!" I asked him why he was running in the first place and he said he felt "someone" tap his shoulder, turned and didn't see anyone so started walking away when he heard foot steps right behind him, which freaked him out and he started running.
One day when I was there I noticed that one of the rocking chairs on his front porch was "rocking" but the other one next to it wasn't, which I thought was odd, then I looked at the trees and saw it wasn't windy but the chair was still rocking, steady like someone was rocking in it, then the rocking chair "leaned" forward like it would if someone was getting out of a rocking chair, held like that for a moment and then went freely before coming to a natural stop, just like it would when someone got off of it. That was crazy shit.
Another time, my brother, myself and my friend were all sitting on the couch in the living room and all three of us turned our head to the left at the same time looking at the same spot, I asked them why they looked and the said the same reason that I did, that it looked like someone had walked into the room but that "he" looked blurry and dark.
At night time his door handles to the rooms would at random start to turn like someone was about to come in but didn't have the strength to turn it all the way and kept trying back and fourth and I'd sit there and look at it as it turned and squeaked over and over. The first night I experienced that I opened the door real quick to see if my friend or his brother was on the other side screwing with me, but nope, both were in their own rooms and it'd have been impossible for anyone to get away fast enough to not be seen.
There was this one spot in my friends room where a red line would form that basically looked like blood and like if someone took a dropper, dropped it on a spot on the wall with enough "liquid" for it to make it's way down the wall a few inches and then dry.
I watched my friend clean the "spot" off myself, then we went to bed, when we woke up, it was back.
Random things in the house would disappear or go missing and usually wound up in the bathtub.
I had a hat that I couldn't find anywhere that I never even took out of my duffel bag one time when I was there and no one even knew I had it with me. I looked high and low for it and couldn't find it, nearly gave up until I went to take a leak and when I was in the bathroom, saw it in the tub.
I know, hard to believe a total stranger but all honest to god stuff that happened to me first hand.
I was a huge doubter and never would have believed any of it had I not experienced it all first hand.
His land was on old Native American lands, we used to find old arrow heads in the woods.
We got to a point where we were all no longer scared by any of it, his Dad put it a good way, they all had lived there and with these experiences for many many years and never once had it ever tried to even remotely do anything to harm them, it was more like a prankster haunting that just liked to get a rise out of people and after being around it long enough it stopped phasing me.
Ever since I stopped knowing my friend (we moved to a different state) I never again experienced anything else like it.