Check out - https://getfindster.com/

We've got them for our five dogs. One time cost - no cell coverage necessary, no sim card needed. 1/2 mile radius coverage in congested areas (city), 3 mile radius in open areas (country). Updates are available as they are released. Haven't used ours with the dogs off-leash outside of our back yard.

Rechargeable batteries last up to about 7 days if you just find/track the dog's location and 2 - 3 days if you want to monitor their various "activities" and some other things.

Someday I hope to be the person my dogs think I am . . .
The only true cost of having a dog is its death.
Someone once said "a nation of sheep will beget a government of wolves."
Shiloh Sharps . . . there is no substitute.
NRA Endowment Member