@Michael *******
Yes, the non-O 90 day, extended annually with 800,000 in the bank is the "normal" way. It'll get you what you are looking for. There are more advanced things you can do such as switching to monthly bank transfers as proof of funds after your first year, but they require planning a year in advance and making sure you never miss a transfer.
Just make sure you get the non-O visa from the Thai embassy BEFORE you go to Thailand, or you won't be able to open a bank account. No bank account, no extensions.