Home security system for apartment ?

A little sad I have to write this but I need recommendations for a reasonably priced home security system.

I’m not thinking it’ll be used much since we’re on the highest floor in the back of a very tucked away complex with virtually no ‘through’ traffic. But I’m getting very worried since husband works nights, and my next door neighbor had someone pounding on her door this morning at 6am.

We asked her about it and if she was alright later, and she had no idea who it was but we both heard 2+ male voices talking loudly at her door....

it’s really starting to creep me out now that she’s told us it happened at 1am too a few months ago with someone trying to coax her out of the apartment, and a while ago we found some of her VERY HEAVY patio furniture moved to an odd position that she said she didn’t do either. (She was away at the time)

We should be able to put a camera in the windows right beside the front/back doors, though husband and I agree we might want one hung up outside to aim near the stairs too.

We’re the only two apartments on this floor and we haven’t experienced any of what she has (yet)

Any that can send video to a computer/phone y’all know of?