Do I need to submit a financial statement when renewing my Non-Immigrant O-A visa in Thailand?

nope doesn't mean that at all 😕

You wouldn't be renewing anything, you have a year entry stamp from a year-long, multi-entry OA visa that you bought in your country,

AND

you have two choices,

1 - you can exit and re-enter the country before the VISA (sticker itself) expires and that will get you stamped in for a whole new year (as long as you have another year of insurance)

OR

2 - you can meet the proof of funds requirement (800K baht in a thai bank account in your name only for 2 months before you apply) and have the year insurance too, by going to the immigration office and apply for a yearly extension for 1900baht.

So if you decide to go for the year extension inside the country the 800K baht needs to be in the account for 2 months on the date you APPLY for the new extension (which you can do when you have 30 days or less left on your current entry stamp)

Will you be applying for a new Non-OA in your home country or an extension of your existing visa inside Thailand?