These instructions direct from the hotel make it sound like it's easy using public transportation, is this not the case?:
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Airport Link + BTS
Bangkok has a new airport link service between Suvarnabhumi International Airport and Phaya Thai, a downtown BTS station. You will need to take the train from the airport to Phaya Thai, and have the ability to choose between two lines:
Normal Line (24 minutes) - stops at 8 stations
THB 40 per person per way
Express Line (20 minutes) - stops at 1 station
THB 150 per person per way
From Phaya Thai, you can take a taxi or the BTS for 4 stations to Phloen Chit, which is where the Hotel is located – this service costs an additional THB 25 per person per way. The total duration of the journey is 40 minutes.
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