Applying fopr Retirement Visa from Australia (Bangkok)

There are many forum discussions regarding this topic but each has their own flavour of questioning. So needless to say I am still confused regarding the process to get the retirement visa. I understand the requirements to get a retirement visa it’s just the procedure/process I am unsure of.

1. Do I apply for the Retirement visa whilst still in Australia or
2. do I apply for a 90 days (O visa (non-Immigrant?)? – but I am not visiting family in Thailand?) in Australia and then once in Thailand I go to a Thailand Immigration office and apply for a 1 year extension for a retirement visa?
3. If option 1 above, how do I prove 800,000 baht in a Thai bank account if I don’t have a Thai bank account or do I need to prove finance in an Australia Bank account? ( I am not going the 65,000 baht monthly income route)
4. If its option 2 above, I assume I open a Thai bank account when I get to Thailand and then transfer the 800,000 baht to that account and then after 2 months go to a Thai immigration to apply for the retirement extension?
5. Do I do the medicals and police clearance whilst still in Australia for option 1 and/or option 2?

Any URL links for my questions I can explore further?