So my airbnb is very small and simple, actually the apartment is big, the guest's room is big, but what the guest see is corridor and bathroom and they are small.
When a guest enters he has his room in front of him, the bathroom at his left, and onother door at his right that he does not not have access to.
I can be there during the day but i sleep at my mothers house.
So most of the time guest check out by themselves, they leave the keys on the table and close the door(without the keys).
For safety i want to install a door sensor, basically if the door opens when I'm not home in a day with no guests or after the last guest has check out i recieve a signal on my phone
So i would put it on the outside door, the brown one, not on the internal white doors. Am i allowed to do that? I don't know if some guests would not understand what it is and complain