We make it a policy for the guest to give us their arrival time and departure time along with the name of each occupant. Because the majority of our guests are coming in from the airport on their way to somewhere else in the state, we've found it is helpful to know when they are arriving and departing. Our onsight manager can be assured the car/s coming onto the property are legit and, will remain awake to help to assure they are able to get into the unit. After red-eye flights, there are those who can't read/or follow the instructions we've sent to them.
The check-in time is after 4 p.m. but if we have guests who have said their plane arrives at 1 a.m. - we move the housekeeping of their apartment to after one that guests are waiting to get into at 4.
If guests are arriving quite late, we also may add breakfast items/coffee, knowing they haven't had time to go to the grocery store before their arrival. Or if the guests are leaving extremely early for a bus or train journey, we can make sure we add some take-away snack items in bags they can have with them on their journey.
We have found this policy extremely helpful, too, if a guest says they are arriving at 11 a.m. and check in is after 4 p.m., it gives us the opportunity to remind them of the check-in time; where they might want to spend those few hours, grocery stores to stock up, etc.