You ask a good question. I use some bluetooth (Victron, SensorPush) and it can make a difference. I have not used my Air Tag in the Escape as yet but where you hide it can make a difference. It can easily be tested in different locations.
Metal will be a good place to avoid, especially placing it next to refrigerator, furnace, water heater etc. Watch electrical area, WIFCO, solar controller. Don’t over think it.
I think the Air Tag will be an useful tool. From my experience it will work best for Apple owners.
Paul and Janet Braun
2003 Toyota 4Runner V8 now 2012 Toyota Sequoia V8
Escape 19' 2010 now 2014 Escape 21'