Just called the Bumrungrad Business Center to check the prices of the 30 day extension. IF you show up during the week, let them get the documents ready and then show back up on Saturday it's 3000baht, BUT if you just walk in on Saturday without having shown up first during the week they charge 3500baht
So in addition to the 1900baht fee for the extension the service charge is 1100baht if you show up early, then go back on Saturday for your appointment, and 1600baht if you just walk in on a Saturday for the 30 day extension.
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