You obviously missed the fact that the OP is seeking advice and suggestions. The best visa of all is the DTV. Cheapest, low maintenance, easy to get. But it's not for everyone is it?
Depends on Embassy/Consulate. I switched from non-O retirement to DTV, and all I did was register a business name, get an Australian Business Number (both of which can be done online very easily and low cost). I nominated my daughter as the "secretary" and she gave me a work contract (template online) stating my duties can be performed remotely in Thailand. The business consults and manages my Australian investment properties. Absolutely no dollar figures were given. I am simply a "remote worker". The approval took three days. Now I've got the five-year visa which beats the crap out of the pedantic non-O 👍👍