The setting is accessible via Property's Main Settings tab
Airbnb and Direct Bookings
Let's use an example of a property with a 3pm check-in time.
--If you set the Booking Lead Time to 1 hour, the latest a person will be able to make a reservation is at 2pm that day, 1 hour before check-in.
--If you want to allow someone to make a same day booking, but after check-in time you will want to use negative numbers for Booking Lead Time.
For example, your check-in time is 3pm, and you want to allow someone to make a booking all the way up until 8pm that night (maybe they got in late and need a place to stay last minute). You know the place is clean and you can offer them access.
In this example, you would want to enter -5 since your check-in time is 3pm and you want people to be able to book 5 hours past your check-in time.
If it's not a same day booking, Airbnb only allows a booking lead time of midnight for 1, 2, 3, or 7 nights before check-in. For example, if you choose Booking Lead Time of 24 hours, it would be 3pm the day before. That works for direct bookings, but Airbnb does not support that. We round up, so in this case the Booking Lead Time would be 2 midnights before (39 hours before check-in).
Note: if the checkbox of "Allow booking request" is chosen, guests who don't meet the Booking Lead Time requirement are not able to Instant Book, but can still send booking request and PMs can accept or decline accordingly.
Vrbo/HomeAway does not do same day bookings
The cutoff time is calculated from midnight on the check-in date in the property's timezone. The check-in time of the property is not taken into account for the cutoff time.
Example: Property has 24-hour cutoff, a guest is searching for a stay with a check-in date of June 19. Any availability for that check-in date will show up on Booking.com until June 18, 23:59 property time. At midnight on the check-in date June 19, all availability with the 24-hour cutoff will disappear.