I realize it's not sold by Best Buy. I also realize it's open box. What i like about it the ability to link to Alexa, Google/Home (I realize it's limited in scope), and IFTTT. I also like the idea that there's a siren.
I'm not sure I understand what you mean about "chinese camera's offer free".
Well, I bought this off eBay for $79.95 less a $5 coupon and like what I see so far.
The way it works is that it automatically senses when someone is home or not. When someone isn't home, it will send a notification when there's movement in the house. Then you become your own monitoring system. You watch the video of your home and if you don't like what you see, you can sound the siren and call the cops right from the app.