in theory you can extend your stay from 180 days for another 180 days once per entry. However in practice it’s just way simpler to “bounce” to another country and return for a fresh 180 day entry.
Alternatively look at getting a DTV visa for the both of you. Easy option for many. It’s a 5 year multiple entry visa and lets you stay for 180 days each time.
Not these days. If your spouse applies for a Non OA from your home country then that embassy ‘may’ issue a “trailing spouse” Non O. Few do. Generally it’s 800k per person in a Thai bank in their name only. Joint accounts may be accepted but the amount would be doubled as they see it as 50% yours 50% the other holder.
That would be pretty normal. They take it to the immigration office and have the visa stamped in. Usually they process many of these a day so it’s easier if the passport holder doesn’t show up.
Go to your local immigration office and ask for the handout how to convert from tourist visa (or exempt) to a in-country Non O. Cost is 2,000 baht.
If you meet all the requirements you’ll get a 90 day Non O visa and when that’s winding down you apply for the yearly extension of stay. Again ask what is required for that. Cost for the extension is 1,900 baht.