Pullman Bangkok G in Silom. Delicious burger joint next to the lobby, awarded rooftop bar & steakhouse on the top floor, wide variety at breakfast, nice local restaurants around the vicinity.
yes but nowadays virtual banks like Revolut and Wise allow you to have a milti-currency account of up to 25 currencies (THB included) with a Visa card. The FX rates are much better than international TT rates - plus there won't be any fees when U use the visa card in the country.
Immigration in Bangkok asked me how long I would stay when I landed 2 weeks ago. I just answered 1 week and they never asked to see my onward ticket. This being said your airline may ask the same question when you check-in in Hanoi