If you already have a valid drivers license from your home country and it has a motorcycle endorsement, you can have have a Thai DL issued in about an hour if you go to a Land Transport Office that isn't very busy.
Assuming you already have a valid license, all they do is test your depth perception, peripheral vision and reflexes. Quick and easy, no written test and they'll print out your new Thai DL on the spot.
Any corner clinic can issue the medical certificate in 10-15 minutes, I don't recall having to supply proof of address when I applied for my Thai DL, but maybe I was just lucky?
Caveat- I got my Thai DL 4 or 5 years ago so things may have changed since then. You are first issued with a one year DL, then it's renewed for a 5 year DL. The cost, if I remember right was something like 200 Baht
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