Great looking project! I haven’t tried to set it up yet as I don’t have the equipment or time right now, but I’m following along with interest!
Out of curiosity, are you aware of FIND?
I stumbled across it the same day I found your post as I was doing a little research on presence detection. It sounds like they could potentially be very complimentary. FIND has a “passive tracking” mode that is vaguely similar to your strategy (from the standpoint that there’s no software installation or configuration requirements on the tracked devices) but it sounds like it has a much slower detection rate (at least in passive mode) than your solution due to it only listening for Wifi broadcasts as opposed actively polling for bluetooth devices the way you do. Where it shines though is it does statistical analysis of the responses allowing it to identify not just presence but specific room locations!
I know I’m just making noise at this point, but the thought of being able to combine the techniques in both your projects…
Anyway, just thought you’d enjoy looking at FIND if you weren’t already aware of it. Keep up the good work!