Why would you not want to continue your retirement visa. The marriage visa Is much more intrusive meaning it cannot be approved at your local immigration office and you need to take pictures of you and your wife in and outside of your house and I think a a recommendation from two neighbors with copy of their I. D. Cards
You will need your Bank book updated every month for the last 12 months showing an international transfer to your account. Then a letter from the bank showing your balance. since you have an O-A visa you will need health insurance
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