Probe walk " new " ground to confirm or eliminate.
You might be surprised what a " nothing" spot turns out to be.
Knock on some doors also.
Worst they can say is no.
1 spot I got access to last year for me and slumlord would be pretty good if they didnt no till the place I bet.
Your eye will get trained eventually to spot them outta the natrual rock that aint been worked.
