What type of tracking devices has been used, with success and reasonable price?

This is not good. I use a GPS on my Dads car but he is not to the point your Husband is. I track him daily to see any signs that he is wandering or getting lost. His car has not one scratch and Mom reports that his driving is still quite competent and he has never gotten lost.

This is no solution but it's the best I can do at the moment and will hopefully let me dive in and get the keys at the first sign of incompetence or danger.

I think your husband is beyond this. He should not be driving. If this happened once it will happen again. The only thing a GPS device will do is help you find the accident. I know I'm gambling a bit with my Dad but you have a losing hand with your husband. Think this through very carefully.

You don't need a tracking device for the car. You need a good hiding place for the keys.

For the personal tracker, check out angel sense website. Looks like the equipment is $60 and the monthly fee is $40. Sends alerts to your smartphone.

My husband, took off today , took me an hour to track him down, he was going home,
not his home, the one he remembers from ages ago, lucky I realized he had left and followed him, with the help of local police and son in law, we found him driving around lost. So yes I need a tracking device for him and the car. I am not ready to put him in an memory care facility.

Are you talking about driving or personal alert?

Give it up, my friend. If you are caring for someone who needs a tracking device, it is time to get that someone admitted into a secure memory care facility.