We have a flight out of athens (to chania) at 5 in the morning on 2nd October. According to metro timetables, there are no trains at night. The only way is taking a cab (which is a bit steep). Should we get a cheap hotel, spend a couple of hours and take a cab? Or is it feasible to spend 4-5 hours in the airport? Will the airport let us enter 4-5 hours earlier?