Hello.
I have on my build one mailbox…and i put inside a 433mhz door sensor, when the postman put the letter he open the door and i receive one message throught telegram, because i have one gateway mqtt inside of my house.
but i have a big problem, i live on 3th floor, and the signal rf433 is very poor, sometimes the signal not arrive.
i thought to use a simple ESP8266 whith one cell battery, but i cant get signal wifi there.
I like the idea, and my way around it is to take the DIY Multisensor from BRUH Automation on YouTube, strip off all components except light component, so every time he opens the door, it’ll send the light spike, updating a sensor in HA, saying go check the mail box. I run it off of a 9v and it a compact enough I can tape it and leave it until I have to get a new battery. My next update will probably be add a battery watcher so it’ll tell me early on I need to change the battery. I didn’t think about using the door sensor until now. That may actually work.