Originally Posted by
Dr. HFH
Depends on the hotel and your status there. SPG, for example, has Your24, which allows you to set your own checkin/checkout time. You then have the room for 24 hour periods starting with your actual checkin time.
Most hotels offer the same for regulars / status members, or at least the early check-in even if it's not necessarily advertised or a published benefit. Whenever I have a very early arrival anywhere, I choose a hotel where I have status and then just try my luck for the early check-in. It works out 90% of the time.