People tend to check in during these times:
Convenient for the airport but the walls were paper thin so I got little sleep before my flight and I found the laminated room inventory with prices for damage to be very unwelcoming.
Nice place for one night between flights. Restaurant is open until 11 pm. Clean and cheap rooms. Friendly stuff. Free transfer from/to suvarnabhumi.
Difficult to find, even for taxi drivers.
Airport shuttle every hour. 24hs service