@Griff, if you are thinking using a gps tracker while training your new pooch I will have one going up for sale in september when the subscription is due as Tina is now well and truly a home dog not the flighty wild street dog she once was, it's a tracktive with collar mount (works well on a harness) with two batteries and two charging leads, I got spares so I could leave a battery and lead on the boat.
I will use it for our september hols (first two weeks) then cancel the subscription as it is due to auto renew a week later, it's given us a lot more confidence for the first off lead walkies, that first unclipping is terrifying even with a 10metre trailing lead on.
She may have dodgy recall still but it's because she is playing/scrounging/scavenging rather than looking to do a proper runner, she now knows she has a very cushy life.