With 20hrs I would question staying at BKK Novotel taking into account your early departure time and wish to beat the airport at 8.00am.

I think better to get a good hotel in town for 2,500-3,500 baht net rather than 4600 baht for the Novotel plus upto a 1,000 baht by taxi if not on the meter.

You can use the money saved by taking a AOT limo for less than 2,000 baht return or save more with a hotel limo deal or take the taxi and save more. Happy to give you a few tips by PM about dealing with BKK taxi drivers and can say the reality is usually a lot less painful then the thought, if you abide by a few common sense rules and tips.

Your travel time to the airport should be about 40-50mins depending on how near you are at the tollway and time of day you go.

Be brave its not that bad.

BTW chances of getting a much better rate are slim as they carefuly calculate the cost of the hotel averse to going into town and they know they have a captive audience of people who are worried about heading into bkk.

It was the same at the Amari airport hotel at the old BKK, Don Muang high prices until now where it is next to nothing.

Just a case of how much you want to save, there are hotels 25 mins from the airport near Petchburi Road for 500 baht and not as bad asyou might think, you pays your money, as they say.