I'm sure your daughter and you will have a great time. People get touchy over legal grey area and what your allowed to do and where. Some people are sticklers, some see digging holes in the ground of abandoned/public places as 'eh, who really cares?' Indifferent to local laws. Its up to you to decide how you feel about it and where you want to try your luck.

I personally have no problem detecting in public places I know nobody lives or cares about regardless of what tax/lot records say. Ive done a few side of the track runs, abandoned schools, big field lots that filled old public pools, riverside hiking trails. As long as you arent making nasty holes its not worth anyone's trouble.. Worst case scenario someone tells you to leave.