If you get the Non-O visa based on being over 50 there are no insurance requirements

You can't hold 2 visas, number of passports is irrelevant

Set up your business alongside your Thai partners. The business needs 2m baht registered capital and must officially employ 4 thais for every foreigner work permit. You can convert the DTV to a Non-B visa at an immigration office inside Thailand which allows you to hold the work permit

Where are you from? The visa isn't important

If you are inside Thailand for 90 consecutive days you need to do a 90 day report. When you do the first one the immigration officer will staple a note in your passport with the date of the next one

You could probably get the 90 day Non-O visa inside America before travelling but you couldn't get either it or an income of it inside Thailand without your wife being present

I assume you mean LTR visa for a Wealthy Pensioner? They will only accept either $80k USD in passive income, or $40k USD in passive income plus an investment in Thailand. Passive income must be actually passive income, it can't me in investment account, pension account etc. Drop the BOI a message, they're very helpful

@Andy **********

correct

That's a really bad idea and risks getting a refusal. Thai consulates expect you to remain in the country you apply from until the process completes and have been known to require proof of this

I believe you have to show the money has been in your account for a full 30 days in Bangkok so if your next statement will show that you'll be good, assuming you also have the other documents. You should get the extension the same day you apply for it. You can only get ONE extension on each entry so you have to leave at the 360 day point, but you can return the next day and repeat the process.