Hi OP,
Have been following this thread with interest as I too have lived in a Victorian property, a flat above a shopping arcade on the SC.
We lived in it twice for various reasons too mundane to mention, but both times we had plenty of weird experiences, including noises from the attic in the wee small hours so loud my ex DH, a big hairy biker, called the police. This wasn't as big an over-reaction as you might think - in some flats like ours there aren't actually fire breaks separating them - in another flat we lived in on the main road round the corner you could go from one end of the road to the other through the attigs IYSWIM. So it seemed possible that someone could have been up there having gained access from another flat. Anyhoo, police went up, had a look around - turns out we did have sealed attics and there was no sign of anything remotely animal or human. They did suggest squirrels but it was a quite towny area with few trees nearby, and I would have expected to have heard them more than once. Very odd indeed - sounded like furniture being moved and dragged. If squirrels wear hobnail boots I could get behind it a bit more.
My DS was about 6 when we moved in the second time, and we moved out when he was about 15. While younger, we once found him downstairs in the morning under the dining table with the chairs pulled in around him. He said he had seen a Victorian lady sitting in front of the doorway to the bathroom. The bathroom had been a bedroom in the past and was quite big; I acted unsurprised and as non chalant as possible and advised him to say hello next time and not worry, but we wondered about the history of the place and why the bathroom door had a bolt on the OUTSIDE......
I twice saw what I thought was my son - once dancing in front of the TV as I passed the lounge door going into the kitchen, but when I stepped back to say "Cool moves dude" he wasn't there and the TV was off. Another time, sitting on the sofa just inside the door reading a newspaper, he crawled past me and I looked up to speak to him - again, nothing there - this was in broad daylight, middle of the day and I was of course sober .....
We had a very shy black and white cat, and one day my Mum and I were having a cuppa mid-morning and a chat in the lounge. We had one of those vibrating stand on things for exercise - my ex DH had been in a sever bike crash before we met and was always trying out things to improve his pain from the injuries - this gadget had been used a couple of times then became the home of the cat igloo which sat on the plate. As Mum and I were chatting, DCat suddenly, and uncharacteristically started stalking from the door into the room. We were surprised but didn't do anything as it was unusual for him to grace us with his presence and didn't want to scare him off. he did the whole ears back, belly to the ground thing into the middle of the room. As he got near to the cat igloo, my Mum and I both heard a weird almost electronic laughing sound - DCat took off like a Harrier Jump jet and left the room at speed without touching the ground. My Mum was the least woo person in the world but confirmed she had heard the noise too, so I said it must be one of DSs toys having a glitch, and very matter of factly checked in, under and around the cat igloo. Nothing to be found........again, broad daylight, sounds of bustle outside, utterly baffling.
I think because we just behaved as though we had invisible lodgers and weren't particularly bothered, any activity was quite mundane. The people who moved in after us however, who didn't know any of this, fared less well, with heavy objects, and once a knife being lobbed around. To my knowledge the flat has been "exorcised" at least twice since we left. I'm quite into the "woo" now, and would love to go back with equipment and see what happens.
Finally, I try to think in terms of ebergy and everything in the world being somehow connected - sort of quantum physics stylee although I know I will be told I don't understand true QP, which I don't but some of what I have read seems plausible. I remain an open minded skeptic really - there are more things in heaven and earth and all that jazz....
Good luck OP - looking forward to seeing your updates.