I've lived in the same house in Southeastern Pennsylvania for the past twenty years. The stone farmhouse was built in two parts, the older half dating to the 1740's and the newer to about the 1850's. My great-great grandparents obtained the property toward the later half of the 19th century and it has been in my family since. During the time that they lived here it operated as large scale hog farm and later they owned their own garbage removal business. My great-grandparents hired local men, both looking for work and others who had committed minor crimes, as means to supplement the work done on the farm. These men sometimes lived on the property, but daily interacted with my family-taking meals in the house, breaks, etc.
As an adult I, and my family, have had several odd encounters. One day during the summer about two years ago I was home alone in the basement doing laundry. We don't have A/C so I had the windows open and the doors unlocked. While in the basement I distinctly heard someone walking across the floor above my head going in the direction of the living room and the kitchen. This was believable enough that I called out for the Dad, thinking that he may have stopped in for a drink or something. No response... So I snuck out the basement door and crept around to the front door thinking that if someone had indeed broken into the house I would be able to see their car, or at least some evidence. No car... So I got my cell phone out of my car and called my Dad. No one had been home; there was no explanation for it. But those footsteps were real; there was weight to them, a distinctive gait and the heavy thud of a boot type shoe.
My mom had a similar experience when she was upstairs folding laundry in her room. She heard the front door open, close, and what she thought was my Dad walking out toward the kitchen. She tried talking to him, but got no response and simply wrote it off to his poor hearing. Later to find out that he was never in the house.
Just a month or two ago I was upstairs getting a shower with the door shut and locked & heard my Dad say, "Hi Pooh (what he calls me) I'm not going with you." He was never in the house.
Aside from the last incident the odd events always occur on the main floor of the home, when we are on the floor above or below. It has sounded distinctly like a man, equipped with weight and boots. Maybe the men are coming home for a meal? I'll tell my great grandmother about it and she automatically gets defensive, I'm crazy, it was just the wind, etc. Maybe she knows something we don't?