@Christine **********
, Unless Chiang Mai does it differently only of you has to meet the financial requirements and the other can 'piggyback' onto their extension based on being married to a foreigner here that is on a long term extension.
One applies for the Non-O based on being over 50 and by meeting the financial requirements and the other applies for the Non-O based on being married to someone who is going to get a long term extension here.
The one that meets the requirements WILL need the 800K baht in a thai bank account in their name only first for the Non-O visa (where the funds don't need to be seasoned) and then once again for the year extension (where the funds need to be seasoned for 60 days before you apply)