Ask HN: How can I find trackers I did not place in my stuff?

By sheer luck I found a Tile BLE tracker in a car I purchased recently. I assume it was put there by the previous owner in case of theft and forgotten. It nonetheless has been destroyed. Now I'd really like to know how you defend yourself against this sort of attack?

I'm not looking to defend against a 3 letter agency or nation-state, but against any low tech stalker, ex, would be thief, or cop without access to Flock cameras type of adversary. Looking for something that would be able to find BLE trackers regardless of platform/company.

I ran a scan using nRF but there is a lot of noise out there and isn't sustainable. Have you found trackers in your stuff? How do you defend against trackers? There are apps out there but it's hard to trust them with the required permissions. Open source would be great. I'm on Android and have "tracker protection" or whatever enabled.