Be sure and get a reentry stamp at immigration before you go. If you’re going to be traveling a lot out of Thailand, get a multiple reentry stamp.
Every time you come back into Thailand, you restart the 90 day report clock.
I just recently went to Laos and went to immigration and asked if I needed a new TM-30 and they told me if I come back to the same address, I don’t need a new one.
In my opinion, for your first year, yes. But it depends on the interest rate.
To get a retirement visa and bank account opened with an agent in Pattaya, it will cost you about 30,000 baht, or roughly $900 at 33.5 baht to dollar exchange rate.
Same exchange rate for 800,000 baht is about $23,900.
At 4% interest you would lose about $960, plus the fees to transfer the funds into Thailand.
And then, you can change to the income method for the next year, doing yourself going forward.