What is the proper step-by-step procedure for obtaining a visa to live permanently in Thailand as an expat married to a Thai citizen?

First step is apply for a non-O Visa based on marriage to a Thai national. Can be applied as an EVisa online or you can check with your local embassy. In either cases you will be required to produce a financial proof and some other paper work, pay a visit to your local embassy website first. Visa is single entry and valid for 90 days of stay.

Second step, arrive in Thailand and open a bank account, if possible with Bangkok Bank, because it has no limits to the amount of money you can transfer from abroad. Within the first 30 days of stay deposit 0 baht as that is what you need to have your visa extended.

When you have 45 or less (some provinces 30) available days left go to immigration and extend the Visa for one year. Again pay a visit to your local immigration office first for the list of requirements. After that keep extending the Visa over and over every year (0 baht in bank 60 days before each re extension).

Last but not least, get as much documentation as possible about stuff like TM30, 90 days report, Re Entry permits and certificates of residence as you are going to need them all.

Chok dee

Kind of an odd time. Thailand offers several visa options and marriage is probably the biggest pain. Also, the Thai government has threaten to tax some monies coming into Thailand, so tax status is a concern. Nobody knows what will happen with that. You may consider getting a longer term visa to see how it plays out and weigh your options carefully.

Contact the Thai Embassy in Canbera. They are very helpful

There are a few options....normally you would apply for a marriage O visa.

This requires proof of capital of 800,000 baht every year.

Leave what?

Live* there...

You may want to look into the Thai Privilege visa program. Formerly known as Elite visa. They offer multi-year packages. They are a little on the expensive side, but it sounds like you have made the commitment and are in a financial position that would enable this option. This is a relatively stress free service. Google them to find out more information.

First priority. Make sure you retain Australian Tax Residency otherwise every single dollar you generate in Australia will be taxed at 32% as you will lose the tax-free threshold. This includes state pension.