Unless you want to spend a full week in a hotelroom, Phuket Sandbox is the way to go for now, unless they reinstate Test & Go tomorrow on the 4th of January. I think it's doubtful they do, but unless you're in a hurry, maybe wait and see.
Now, I don't actually know how the Phuket Sandbox works 100%.
But I think you book a hotel, and then book tests and transportation through the hotel again. But hoping someone can chime in and correct me on this if I'm wrong.
Here's a list of hotels certified for the Phuket Sandbox
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