No that's a standard rate our Thai friends poured over the bill with a fine tooth comb, and it was in line with the estimated cost we were given on arrival, great service at a good hospital of international standard. Just saying don't be tempted to save a few bucks by not taking out a policy. Mine is on the credit card I use, so at least we will get FF points.
AS others say, use the Thai passport, even if expired, she can even get in with her ID card in an emergency, You can get a new passport in 24 hours. MBK has a walk in, several more all around, you can lodge and have it express posted back in next morning. My wife did it in Jan, and 2 daughters 3 months ago.
I would really look into where you buy, some Condos are cheap, because owners of others aren't paying the ongoing fees, so no maintenance being done, and the rules stop legal action against them, so the whole building suffers.
You dont state the Type of work you do, so I assume you can both work remotely, so next in my mind is schooling for your children. Most International schools are good but expensive. Next is the Environment. I would pick schools then location and type of home, ie apartment, Condo, free standing house. The visa's as other say can be applied for. For a good school allow $US40k pa per child then ++ for every thing else.
I am here from Australia, my bank provides fee free credit and debit cards. It pays the 220bht ATM fee. I have an App that gives me the daily exchange rate. I have Google wallet on my phone and Villa and Big C Supermarket chains allowed me to swipe. For all the hassle involved I don't bother carrying heaps of cash. Unless you are in the country side order drinking and smoking in shady bars. I wouldn't bother with heaps of cash. In Bangkok I use a travel card on the train and the Grab app for most taxi rides. The motor bike rides cost 20-25 bht. I just drawer 5K from the ATM as needed. Yesterday my bank exchange rate was 22.
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on the 3000bht I withdrew. The ATM offer was 21.
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, and the money changer offer was 21.9. The Australian bank official rate was 22.9. Do yourself a favour check your banks and get a card with no fees, large amounts of cash also leave you open to having it stolen.