You'll have to insist the driver to switch on the meter. No. 29 and 59 will be suitable. Taxi fare is 200 to 300 Baht. Hotel Limousines are 500 Baht. Airport departure tax is 200 Baht for international travellers.
Reservations are necessary for convenience.
For Kanchanaburi depart from Bangkok Noi Railway Station just across the river at 8.00 A.M. and 1.55 P.M. daily. No reservation needed. There is en route food, music and video for entertainment. Booking is necessary for Chiangmai, Phuket and Samui etc. No booking necessary.