@Rob *********
not sure what country you are from but check to see if your embassy does an income verification letter. That means you don't need to deposit the 800K THB. They also validate your wedding certificate so you can add your wife as a trailing spouse. I know Canada still does this but not sure what other countries do.
Also if you want to go the trailing spouse route, so you both don't have to open a bank account, it's better if you both arrive on a Non O if possible.