Upstairs Neighbor stalking me

Hello! I need some creative minds out there to chime in. I have an upstairs neighbor that has harassed and stalked me for going on 4 years now. It started out as pounding on the floor super hard. Then when I didn't react, he would slam his couch down onto his floor repeatedly at 4 in the morning. This was terrifying as I didn't know this dude and he had just moved in. I was so scared cuz I thought, what kind of psychopath would do this to someone right after he moved in and completely unprovoked? This was happening all throughout the day everyday.

I had a friend over and I had my door open and got up to close it. I guess when he heard me close the door he thought she left because almost instantly, he started stomping as hard as he could right over the living room and then running back and forth to the bedroom stomping as hard as he could. My glasses in the cupboard were clanking! And I live in a plaster building! When I first told her about his stomping and harassment, she blew me off as being too sensitive to sounds but as soon as he did it when she was here, her jaw dropped. I said, "so, am I really that sensitive to sound?" She apologized to me for not taking me seriously. I asked her to write a letter to my landlord and she did. My landlord's reply was , "I don't believe you." I told her to come over and she could witness it herself but she refused.

Shortly after that incident, he started following me from room to room always seeming to know where I was in my apartment. If I walked to the kitchen, so did he directly above me the entire way. If I stopped walking, he stopped too. When I started walking again, so did he. I am extremely aware of how I walk when at home becuz I've lived in both upstairs and downstairs apartments most of my life. I walk practically silently so it would be impossible for him to hear me walking...especially from upstairs.

Then he started randomly showing up on street corners or parked on a street that I may be walking down with my dog. He would wait till I saw him then he'd speed off. Everytime I got my dog ready...silently...to go on a walk, he was already outside hiding and making stupid noises to scare my dog. It didn't matter what time of day or night I took my dog out to potty, he was always awake and following me thru the house. This dude NEVER sleeps!

He will react to things I do or say out loud but nowhere near loud enough to be heard under normal circumstances. I've tested this out many times so I can make sure I'm not just imagining all of this. I've called him horrible names quieter than a normal speaking voice and he will pound the hell out of the floor directly above me.

He singles out my dog if he doesn't get a response from me. He will go to the room she is in and stomp so hard and scare her so bad that she has wet herself many times.

Too many incidents to just be coincidences. He can see and hear in my home. I don't know how. He's never (that I know of) been in my home so he couldn't have planted cameras but I know he has something somewhere. I've looked and looked but I can't see anything and I'm too scared to look too thoroughly because if I do, he 'punishes' me by scaring the crap out of my dog. I have cameras of my own but I've never seen him or anyone else in my home. He even mounted a camera outside his window facing directly down looking right onto my front porch! So he sees me leaving and knows when I'm back!

My poor dog lives in a constant state of fight or flight. I want nothing more than to move but I don't have money for a security deposit and availability isn't easy to come by in California.

Does anyone know how he could possibly be seeing me and hearing me? What kind of cameras or other technology could he be using?

Anyone have any suggestions or advice? I don't need anyone telling me I need my head examined until you bring your ass over here and deal with what I've had to live with for 3 years.

I've tried to record him but he sees me trying to do he will go in a different room and stomp cuz we can hear it but it doesn't pick up well at all when recorded.

What kind of sadistic, societal reject does this every single day for years? You would think he'd get bored but he is extremely obsessed! My dog and I have been traumatized beyond repair. The only way I can shower is in complete darkness in the middle of the night, and quite honestly I don't know that even when I move, I'll be able to go back to showering during the day with lights on.

I really need help. If someone can help me out, I would be the most grateful person in the world!