Schwab rebated me $6.22 or so for the 220 THB ATM fee on the 31st. So good to know I don't have to withdraw like 10,000 THB at a time as some suggested, to spread out the ATM fees.
Finishing up a 5-night stay in Bangkok. I chose to stay near the Sathorn pier so that I could get to the Grand Palance and Wat Pho area fairly easily.
It is also near a BTS station but I didn't get to use the SkyTrain and MRT until today. Mostly been using the ferries or the bus, relying heavily on Google Maps. But Google Maps gives bus numbers like 25-something. Today I boarded bus marked 25 and it was not going in the direction that Google Maps suggested. In fact I don't think I've seen any of the buses with the hyphenated line numbers.
The transitbangkok.com site requires you to enter either station names or bus stop names, so you have to look at Google Maps anyways.
So buses were a mixed bag, easy enough to get to Chinatown or Grand Palace, confusing elsewhere.
Didn't try taxis but I did use Grab once, which was brilliant, a surge 210 THB ride around 5 PM. It was maybe 8 kilometers but took 30-40 minutes through traffic. But the air-conditioning was on full blast so it was a relief to get out of the heat after a long day of slogging through it. Plus used a card, so made thing easier than digging for coins.
The ferries were nice, especially the blue flag ones which had air-conditioned compartments, also bigger craft and smoother rides than the orange flag boats which were smaller.
All in all, if you don't mind spending more and there's good Grab availability, that might be the way to go, limit dealing with cash that way and easier to navigate.
Of course Chiang Mai and Phuket may change my opinion.