To be fair it may take time and effort but im sure they would get some permission, some of my permission i have now i gained when i was 14 yrs old, i used to get round the local farms and knock on doors, always dressed respectful, none of this trackies and trainers, always spoke politely anyhow its funny how quick you can rack up permission when you have been on one spot in the area it is getting your foot in the door, Its always good to have a bit of common ground like when i ask for permission i will usually just mention i beat on whoevers and do pest control on wherever. Its all about attit