Simple car tracker - any recommendations?

[andy.s.964]

I'm looking for a simple, self powered GPS tracker that can be tucked away in my classic car. I'd be happy to replace the battery every few months if necessary. Key features would be...

Minimal ongoing monitoring costs (if necessary)
Movement alert setting
Dial up checking of current location with integrated smartphone/computer mapping

I've seen some discussion on here, but nothing that really stands out in terms of recommendations.

Any suggestions please?