My advice is do not use the scammers saying they can do it and you don't need to go to dot they will do everything, tests paperwork etc. government has warned about this scam.
again never been asked but they can ask for proof of 20,000baht or equivalent in your own currency. I always have at least 1000aud on me. Cards get lower rate and $9 fee every time withdraw cash.
Australians don't need a visa currently for as I explained 60 days can enter visa exempt.
MTV is multiple entry tourist visa, every time you enter during the 6 months it's valid for you get 60 days plus can extend. Even enter the day before it expires you get the 60 days